f

Quest for Bugs – The Constrained-Random Predicament

Optimize Regression Suite, Accelerate Coverage Closure, and Increase hit count of rare bins using Xcelium Machine Learning. It is easy to use and has no learning curve for existing Xcelium customers. Xcelium Machine Learning Technology helps you discover hidden bugs when used early in your design verification cycle.(read more)




f

5X “Time Warp” in Your Next Verification Cycle Using Xcelium Machine Learning

Artificial intelligence (AI) is everywhere. Machine learning (ML) and its associated inference abilities promise to revolutionize everything from driving your car to making your breakfast. Verification is never truly complete; it is over when you run...(read more)




f

Data Integrity for JEDEC DRAM Memories

 

With the DRAM fabrication advancing from 1x to 1y to 1z and further to 1a, 1b and 1c nodes along with the DRAM device speeds going up to 8533 for Lpddr5/8800 for DDR5, Data integrity is becoming a really important issue that the OEMs and other users have to consider as part of the system that relies on the correctness of data being stored in the DRAMs for system to work as designed.

It’s a complicated problem that requires multiple ways to deal with it.

Traditionally one of the main approaches to deal with data errors is to rely on the ECC. ECC requires additional memory storage in which the ECC codes will calculated and stored at the time of memory write to DRAM. These codes will be read back along with the memory data during to the reads and checked against the data to make sure that there are no errors. Typical ECC schemes use Hamming code that provide for single bit error correction and double bit error detection per burst. Also, while several of previous generation of DRAM required Host to keep aside system memory for ECC storage latest DRAMs like Lpddr5 and DDR5 support on die ECC as part of the normal DRAM function that can be enabled using mode registers. DDR5 further requires Host to run through an ECC Error Check and Scrub (ECS) cycle on an average every tECSint time (Average Periodic ECS Interval) to prevent data errors.

Not meeting the DRAM Refresh requirement is a major reason that can lead to loss of data. This could be challenging as the PVT variation can cause the refresh requirement to change over time. Putting the DRAM in Self Refresh mode can help off-loading Refresh tracking responsibilities to DRAM but may prevent Host to do other scheduling optimizations and should be carefully considered.

Some of the other things that can affect the DRAM data are

  1. Row hammer where same or adjacent rows are activated again and again leading to loss or changing of data contents in the rows that has not being addressed. Latest DRAMs like Lpddr5/Ddr5 support Refresh Management (including DRFM and ARFM) that allows the Host to compensate for these problems by issuing dedicated RFM commands helping DRAMs deals with potential Data loss issues arising out of Row hammer attacks.
  2. Device temperature is another important factor that the Host needs to be aware of and if the application requires DRAM to operate at elevated temperature. The user needs to check with DRAM Vendor on the temperature range that DRAM can still operate. Data integrity at thresholds greater than certain temperature is not assured regardless of refresh rate unless DRAM is manufactured to withstand that.
  3. Loss of power to DRAM will cause DRAM to lose all its contents. If this is a real concern for the system designer, they should consider using NVDIMM-N devices which has an onchip controller and a power source which is just enough to allow the DRAM contents to be copied into a backup non-volatile memory before power is lost. When the power is stored back, the stored memory contents in the non-volatile memory will be written back to the DRAM and system can continue to operate as it was before the power loss event occurred.

For transmissions and manufacturing errors DRAMs support additional features like CRC, DFE, Pre-Emphasis and PPR which will be covered in the next blog.

Cadence MMAV VIPs for DDR5/DDR5 DIMM and LPDDR5 are compressive VIP solutions and supports all of the above-listed Data integrity features including support for ECC error injection and SBE correction/DBE detection to assist with the verification challenges dealing with data integrity issues.

More information on Cadence DDR5/LPDDR5 VIP is available at Cadence VIP Memory Models Website.

Shyam 




f

Cadence in Collaboration with Arm Ensures the Software Just Works

The increase in compute and data-intensive applications and the need for lower power consumption have resulted in a rapidly growing number of Arm-based devices in various market segments; this requires fast time to market (TTM) and support for off-t...(read more)




f

Jasper C2RTL App for Datapath Verification

Ensuring that the RTL designs correctly implement the C++ algorithmic intent in every circumstance is difficult to achieve with conventional verification. Learn more how Jasper C2RTL App helps to perform equivalence checking with 100x performance improvement(read more)





f

Coalesce Xcelium Apps to Maximize Performance by 10X and Catch More Bugs

Xcelium Simulator has been in the industry for years and is the leading high-performance simulation platform. As designs are getting more and more complex and verification is taking longer than ever, the need of the hour is plug-and-play apps that ar...(read more)




f

JEDEC UFS 4.0 for Highest Flash Performance

Speed increase requirements keep on flowing by in all the domains surrounding us. The same applies to memory storage too. Earlier mobile devices used eMMC based flash storage, which was a significantly slower technology. With increased SoC processing speed, pairing it with slow eMMC storage was becoming a bottleneck. That is when modern storage technology Universal Flash Storage (UFS) started to gain popularity. 

UFS is a simple and high-performance mass storage device with a serial interface. It is primarily used in mobile systems between host processing and mass storage memory devices. Another important reason for the usage of UFS in mobile systems like smartphones and tablets is minimum power consumption. 

To achieve the highest performance and most power-efficient data transport, JEDEC UFS works in collaboration with industry-leading specifications from the MIPI® Alliance to form its Interconnect Layer. MIPI UniPro is used as a transport layer, and MIPI MPHY is used as a physical layer with the serial DpDn interface. 

 

UFS 4.0 specification is the latest specification from JEDEC, which leverages UniPro 2.0 and MPHY 5.0 specification standards to achieve the following major improvements:

  • Enables up to 4200 Mbps read/write traffic with MPHY 5.0, allowing 23.29 Gbps data rate. 
  • High Speed Link Startup, along with Out of Order Data Transfer and BARRIER Command, were introduced to improve system latencies. 
  • Data security is enhanced with Advanced RPMB. Advance RPMB also uses the EHS field of the header, which reduces the number of commands required compared to normal RPMB, increasing the bandwidth. 
  • Enhanced Device Error History was introduced to ease system integration. 
  • File Based Optimization (FBO) was introduced for performance enhancement. 

Along with many major enhancements, UFS 4.0 also maintains backward compatibility with UFS 3.0 and UFS 3.1. 

JEDEC has just announced the UFS 4.0 specification release, quoting Cadence support as a constant contributor in the JEDEC UFS Task Group, actively participating in these specifications development.  

With the availability of the Cadence Verification IP for JEDEC UFS 4.0, MIPI MPHY 5.0 and MIPI UniPro 2.0, early adopters can start working with the provisional specification immediately, ensuring compliance with the standard and achieving the fastest path to IP and SoC verification closure.  

More information on Cadence VIP is available at the Cadence VIP Website. 

 

Yeshavanth B N 




f

Flash Toggle NAND 4.0 in a Nutshell

NAND Flash memory is now a widely accepted non-volatile memory in many application areas for data storage such as digital cameras, USB drive, SSD and smartphones. One form of NAND flash memory, Toggle NAND, was introduced to transmit high-speed data asynchronously thus consuming less power and increasing the density of the NAND flash device. 

The initial Toggle NAND versions had memory arranged in terms of SLC (Single Level Cell) or MLC (Multi Level Cell) mode that was considered as a 2D scalar stack and their frequency of operation was also less. The ever-growing demand of high memory capacity and high throughput required further research in the areas like the shrinking size of cell, performance to fill-in these gaps.

Some of these new requirements were incorporated, leading to newer versions of Toggle NAND, namely 3.0 and 4.0, with a re-arrangement of the internal memory developing a 3D layer of memory. With such structures, higher capacity of the memory was possible, but performance was the primary challenge as the latency of the write/read of memory quadrupled with the same frequency.

The key to improving the performance and run the device at very high speed in low power mode was to enhance the frequency of operation for faster read/writes to the memory and reduce the voltage levels.

But with every technology advancement comes some other problems, the next being the data sampling at that high frequency that can cause setup/hold time issues. To overcome these concerns, different types of trainings on the signal interface were made mandatory that shall assist in proper sampling of the data. Few other features for improving the integrity of the signals were added.

The current set of commands were applicable to access the SLC and MLC memory modes but with the 3D layering, these commands were lacking access to the entire set of TLC (Triple Level Cell) and QLC (Quad Level Cell) memory modes. Thus, more commands were required to make sure that the 3D layering was fully written/read.

Main features of Toggle NAND 4.0 :

  • High Density of Memory
  • High Frequency of operation, greater than 800 MHz
  • Data Trainings

Cadence Verification IP for Flash Toggle NAND 4.0 is available to support the newer version of Flash Toggle NAND 4.0, allowing to simulate the memory device for efficient IP, SoC, and system-level design verification. Semiconductor companies can start using it to fully verify their controller design and achieve functional verification closure on it within no time. 
 
Gaurav 




f

BoardSurfers: Optimizing RF Routing and Impedance Using Allegro X PCB Editor

Achieving optimal power transfer in RF PCBs hinges on meticulously routed traces that meet specific impedance requirements. Impedance matching is essential to ensure that traces have the same impedance to prevent signal reflection and inefficient pow...(read more)




f

IC Packagers: Workflows That Work for You

New IC packaging workflows in Cadence Allegro X layout tools allow you to follow a guided path from starting a design through final manufacturing. The path is there to ensure that you don’t miss steps and perform actions in the optimal order. W...(read more)




f

BoardSurfers: Some Wisdom from Designing for a High-Volume Production OEM

At what stage in the design cycle do you start to think about the PCB material costs? What about the costs to assemble the PCB? Once a design becomes successful, should you then redesign it to achieve a scalable product? Placing components and routi...(read more)




f

OrCAD X – The Anytime Anywhere PCB Design Platform

OrCAD X is the next-generation integrated PCB design platform. It brings to you a powerful cloud-enabled design solution that includes design and library data management integrated with the proven PCB design and analysis product portfolio of Cad...(read more)




f

The Mechanical Side of Multiphysics System Simulation

Introduction

Multiphysics is an integral part of the concepts around digital twins. In this post, I want to discuss the mechanical aspects of multiphysics in system simulations, which are critical for 3D-IC, multi-die, and chiplet design.

The physical world in which we live is growing ever more electrified. Think of the transformation that the cell phone has brought into our lives, as has the present-day migration to electronic vehicles (EVs). These products are not only feats of electronic engineering but of mechanical as well, as the electronics find themselves in new and novel forms such as foldable phones and flying cars (eVOTLs). Here, engineering domains must co-exist and collaborate to bring about the best end products possible.

Start with the electronics—chips, chiplets, IC packaging, PCB, and modules. But now put these into a new form factor that can be dropped or submerged in water or accelerated along a highway. What about drop testing, aerodynamics, and aeroacoustics? These largely computational fluid dynamics (CFD) and/or mechanical multiphysics phenomena must also be accounted for. And then how does the drop testing impact the electrical performance? The world of electronics and its vast array of end products is pushing us beyond pure electrical engineering to be more broadly minded and develop not only heterogeneous products but heterogeneous engineering teams as well.

Cadence's Unique Expertise

It's at this crossroad of complexity and electronic proliferation that Cadence shines. Let's take, for example, the latest push for higher-performing high-bandwidth memory (HBM) devices and AI data center expansion. These technologies are growing from several layers to 12, and I can't emphasize enough the importance of teamwork and integrated solutions in tackling the challenges of advanced packaging technologies and how collaboration is shaping the future of semiconductor innovation and paving the way for cutting-edge developments in the industry.

These layered electronics are powered, and power creates heat. Heat needs to be understood, and thus, the thermal integrity issues uncovered along the way must be addressed. However, electronic thermal issues are just the first domino in a chain of interdependencies. What about the thermal stress and warpage that can be caused by the powering of these stacked devices? How does that then lend to mechanical stress and even material fatigue as the temperature cycles from high to low and back through the use of the electronic device? This is just one example in a long list of many...

Cadence Multiphysics Analysis Offerings

The confluence of electrical, mechanical, and CFD is exactly why Cadence expanded into multiphysics at a significant rate starting in 2019 with the announcement of the Clarity 3D Solver and Celsius Thermal Solver products for electromagnetic (EM) and thermal multiphysics system simulations. Recent acquisitions of Numeca, Pointwise, and Cascade (now branded within Cadence as the Fidelity CFD Platform) as well as Future Facilities (now the Cadence Reality Digital Twin product line) are all adding CFD expertise. The recent addition of Beta CAE brings mechanical multiphysics to the suite of solutions available from Cadence. The full breadth of these multiphysics system analyses, spanning EM, thermal, signal integrity/power integrity (SI/PI), CFD, and now mechanical, creates a platform for digital twinning across a wide array of applications. You can learn more by viewing Cadence's Reality Digital Twin platform launch on the keynote stage at NVIDIA's GTC in March, as well as this Designed with Cadence video: NV5, NVIDIA, and Cadence Collaboration Optimizes Data Centers.

Conclusion

Ever more sophisticated electronic designs are in demand to fulfill the needs of tomorrow's technologies, driving a convergence of electrical and mechanical aspects of multiphysics in system simulations. To successfully produce the exciting new products of the future, both domains must be able to collaborate effectively and efficiently. Cadence is fully committed to developing and providing our customers with the software products they need to enable this electrical/mechanical evolution. From EM, to thermal, to SI/PI, CFD, and mechanical, Cadence is enabling digital twinning across a wide array of applications that are forging pathways to the future.

For more information on Cadence's multiphysics system analysis offerings, visit our webpage and download our brochure.




f

10 Most Viewed Posts in Cadence Community Forum

Community engagement is a dynamic concept that does not adhere to a singular, universal approach. Its various forms, methods, and objectives can vary significantly depending on the specific context, goals, and desired outcomes. Whether you seek assis...(read more)




f

BoardSurfers: Optimizing Designs with PCB Editor-Topology Workbench Flow

When it comes to system integration, PCB designers need to collaborate with the signal analysis or integrity team to run pre-route or post-route analysis and modify constraints, floorplan, or topology based on the results. Allegro PCB Edito...(read more)




f

Allegro X APD: SPB 23.1 release —Your freedom to design boldly!

Cadence is super excited to announce SPB 23.1 release —Your freedom to design boldly 

These tools help engineers build better PCBs faster with the new 3D engine and optimized interface.  

We have been hard at work to bring you this release and believe that it will help you take control of the PCB design process with the powerful new features in Allegro X APD like: 

  • Packaging Support in 3DX Canvas 

  • 3DX Wire DRCs 

  • Aligning Components by Offset 

  • Text Wizard Enhancements 

  • Device File Reuse for Existing Components for Netlist and Logic Import 

 

Watch this space to know all about What’s New in SPB 23.1.  

 

Regards 

Team PCBTech 

Cadence Design System 

For individuals, small businesses, or teams, START YOUR FREE TRIAL. 

 




f

Multiple touch points for bond wires on a die pin

Does anyone know whether it is possible to have multiple contact points for a bond wire on a large die pad? Note: This is different from adding multiple wires which I will also be doing. I need to add multiple bond connections to the same large die pad for redundancy connections to each pad for each wire. I have a large die pad which I need to have 5 wires with each wire having 3 bond connections to the same die pad.




f

Aligning Components using Offset Mode in Allegro X APD

Starting SPB 23.1, in Allegro X PCB Editor and Allegro X Advanced Package Designer, you can align components by using offset mode. Earlier only spacing mode was available.

Follow these steps to Align Components using Offset Mode:

  1. Set Application Mode to Placement Edit.
  2. Drag the components that need to be aligned and right-click and choose Align Components.
  3. Now, in the Options tab, you will notice Spacing Section with Equal Offset. You can equally and individually offset the components by using the +/- buttons for increment or decrement.




f

How to reuse device files for existing components

Have you ever encountered ERROR(SPMHNI-67) while importing logic? If yes, you might already know that you had to export libraries of the design and make sure that paths (devpath, padpath, and psmpath) include the location of exported files.  

Starting in SPB23.1, if you go to File > Import > Logic/Netlist and click on the Other tab, you will see an option, Reuse device files for existing components. 

After selecting this option, ERROR(SPMHNI-67) will no longer be there in the log file, because the tool will automatically extract device files and seamlessly use them for newly imported data. In other words, SPB_23.1 lets you reuse the device / component definitions already in the design without first having to dump libraries manually. An excellent improvement, don’t you think?  




f

How to add wirebond profile to a die pin?

Starting SPB 23.1, a new pin property, WIREBOND_PROFILE_NAME is introduced. This property can be used to define a wirebond profile to a die pin. When adding a wirebond, the pin will use the profile defined in the WIREBOND_PROFILE_NAME property associated to the die pin.

Assign the WIREBOND_PROFILE_NAME property to the die pin using Edit > Properties and set the desired wirebond profile name in the Value field.

The following image displays the WIREBOND_PROFILE_NAME property assigned to the pin and wire profile of the Wire Bond for that pin.




f

Allegro: Tip of the Week : Push Connectivity

At times, there might arise a condition in the design where you need to push the net of selected pins to all its physically connected objects. For example, a few pins are updated with a new net, and it is required to push the new net to all its connected objects. At times, you might update the die or copy routing to other components, when a portion of routing gets the wrong net.

To propagate the net of the pin to all its physically connected objects, Allegro X APD uses the standalone command, Push Connectivity.

You can call the command through Logic > Push Connectivity.

Alternately, you can use the push connectivity command at the command line. Once the command is active, it lets you select pins or symbols that will be used to push net connectivity to all connected objects.

Presently, dynamic shapes and filled rectangles are not considered as part of connectivity. Static shapes are supported.




f

modify bump and export the modified bump

hello, help me!

There are many change in the bump design. I want to design bump by APD.

The bump(die) is a stagger , create it by die generator. 

Because,the pin is not isometric. In order to RDL routing, so the bump is not isometric.

move the symbol pin in APD symbol edit(as show in the picture),  and selected symbol RBM write device file, write library symbol.

Export the bga text( bga text out) ,But the bump is not modified, the bump is still stagger.

Can you help me!

pitch2> pitch1

thanks




f

Find Routing problem (Route Vision) and quickly to fix these problems

The vision manager is good tool for routing check. but no quickly or effective  tool to fix or optimize this  problems to be optimized.

For example, parallel Gap less than preferred, min seg/Arc length,uncoupled diff-pair segs,and so on.

I only know use spread between voids to fix the non-optimized segs. in fact it is inefficient.

the parallel gap less than preferred is only to slice evry trace, its inefficient.

If i set the paraller gap less than 50um, Is there any tool to quickly fix these problems(gap less than 50um)?

For other problems,i can use tool to quickly fix the min seg/Arc length,uncoupled diff pair segs,accoding to select by polygon or select  by windows.




f

DFA check space of compont to BGA ball or BGA PAD in APD

Hi,

There are mang components in BGA ball side of flipchip package.

Are there DFA check space of compont body or pin soldermask to BGA ball or BGA PAD or bga  soldermask in allegro APD?

I only find space of compont to compont in APD DFA. 




f

Allegro X APD - Tip of the week: Wondering how to set two adjacent layers as conductor layers! Then this post should help you.

By default, a dielectric must separate each pair of conductor layers in the cross-section of a design. In rare cases, this does not represent the real, manufactured substrate.

If your design requires you to have conductor layers that are not separated by a dielectric (such as, for half-etch designs), there is a variable that needs to be set in Allegro X APD. You must set this by enabling the variable icp_allow_adjacent_conductors. This entry, and its location in the User Preferences Editor, are shown in the following image.

The Objects on adjacent conductor layers do not electrically connect together, automatically. A via must be used to establish the inter-layer connections.

When enabling this option, it is recommended to exercise caution because excluding dielectric layers from your cross-section can lead to inaccurate calculations, including the calculations for signal integrity and via heights. It is important that your cross-section accurately reflect the finished product to ensure the most accurate results possible. Any dielectric layers present in the manufactured part need to be in the cross-section for accurate extraction, 3D viewing, and so on.

Let us know your comments on the various designs that would require adjacent conductor layers.




f

Allegro X APD : Tip of the Week: ‘Auto-blank other rats’ feature

When working on a complex design, it is common to have very many net ratlines. Quantities like 1000 ratlines are possible. It can result in a cluttered view while routing. Therefore, it is useful to make all other ratlines invisible while routing interactively. You would like to make all ratlines visible again when each route action is completed.

You can easily do this by enabling the Auto-blank other rats option during routing. When enabled, all rats other than the primary ones are suppressed during the Add Connect command.




f

How to execute APD+ embedded function in my form?

Hello, SKILL experts. 

I'm studying SKILL language to build some useful function in APD+.

Now, I want to execute 'Import Sub-drawing' function in new form.

But I cannot find how to do execute APD+ embedded function in a field of new form. 

Has anyone experienced this or idea to solve this problem? 




f

How to transfer etch/conductor delays from Allegro Package Designer (APD) to pin delays in Allegro PCB Editor

The packaging group has finished their design in Allegro Package Designer (APD) and I want to use the etch/conductor delay information from the mcm file in the board design in Allegro PCB Designer. Is there a method to do this?

This can be done by exporting the etch/conductor data from APD and importing it as PIN_DELAY information into Allegro PCB Editor.

If you are generating a length report for use in Allegro Pin Delay, you should consider changing the APD units to Mils and uncheck the Time Delay Report.

In Allegro Package Designer:

  1. Select File > Export > Board Level Component.
  2. Select HDL for the Output format and select OK.

       3. Choose a padstack for use when generating the component and select OK.

This will create a file, package_pin_delay.rpt, in the component subdirectory of the current working directory. This file will contain the etch/conductor delay information that can be imported into Allegro.

In Allegro PCB Editor:

  1. Make sure that the device you want to import delays to is placed in your board design and is visible.
  2. Select File > Import > Pin delay.
  3. Browse to the component directory and select package_pin_delay.rpt. The browser defaults to look for *.csv files so you will need to change the Files of type to *.* to select the file.
  4. You may be prompted with an error message stating that the component cannot be found and you should select one. If so, select the appropriate component.
  5. Select Import.
  6. Once the import is completed, select Close.

Note: It is important that all non-trace shapes have a VOLTAGE property so they will not be processed by the the 2D field solver. You should run Reports > Net Delay Report in APD prior to generating the board-level component. This will display the net name of each net as it is processed. If you miss a VOLTAGE property on a net, the net name will show in the report processing window, and you will know which net needs the property.




f

Maximizing Display Performance with Display Stream Compression (DSC)

Display Stream Compression (DSC) is a lossless or near-lossless image compression standard developed by the Video Electronics Standards Association (VESA) for reducing the bandwidth required to transmit high-resolution video and images. DSC compresses video streams in real-time, allowing for higher resolutions, refresh rates, and color depths while minimizing the data load on transmission interfaces such as DisplayPort, HDMI, and embedded display interfaces.

Why Is DSC Needed?

In the ever-evolving landscape of display technology, the pursuit of higher resolutions and better visual quality is relentless. As display capabilities advance, so do the challenges of managing the immense amounts of data required to drive these high-performance screens. This is where DSC steps in. DSC is designed to address the challenges of transmitting ultra-high-definition content without sacrificing quality or performance. As displays grow in resolution and capability, the amount of data they need to transmit increases exponentially. DSC addresses these issues by compressing video streams in real-time, significantly reducing the bandwidth needed while preserving image quality.
 

DSC Use in End-to-end System

DSC Key Features

  • Encoding tools:
    • Modified Median-Adaptive Prediction (MMAP)
    • Block Prediction (BP)
    • Midpoint Prediction (MPP)
    • Indexed color history (ICH)
    • Entropy coding using delta size unit-variable length coding (DSU-VLC)
  • The DSC bitstream and decoding process are designed to facilitate the decoding of 3 pixels/clock in practical hardware decoder implementations. Hardware encoder implementations are possible at 1 pixel/clock.
  • DSC uses an intra-frame, line-based coding algorithm, which results in very low latency for encoding and decoding.

DSC encoding algorithm
 

  • Compression can be done to a fractional bpp. The compressed bits per pixel ranges from 6 to 63.9375.
  • For validation/compliance certification of DSC compression and decompression engines, cyclic redundancy checks (CRCs) are used to verify the correctness of the bitstream and the reconstructed image.
  • DSC supports more color bit depths, including 8, 10, 12, 14, and 16 bpc.
  • DSC supports RGB and YCbCr input format, supporting 4:4:4, 4:2:2, and 4:2:0 sampling.
  • Maximum decompressor-supported bits/pixel values are as listed in the Maximum Allowed Bit Rate column in the table below

  • DP DSC Source device shall program the bit rate within the range of Minimum Allowed Bit Rate column in the table:

          


Summary

Display Stream Compression (DSC) is a technology used in DisplayPort to enable higher resolutions and refresh rates while maintaining high image quality. It works by compressing the video data transmitted from the source to the display, effectively reducing the bandwidth required. DSC uses a visually lossless algorithm, meaning that the compression is designed to be imperceptible to the human eye, preserving the fidelity of the image. This technology allows for smoother, more detailed visuals at higher resolutions, such as 4K or 8K, without requiring a significant increase in data bandwidth.

More Information

  • Cadence has a very mature Verification IP solution. Verification over many different configurations can be used with DisplayPort 2.1 and DisplayPort 1.4 designs, so you can choose the best version for your specific needs.
  • The DisplayPort VIP provides a full-stack solution for Sink and Source devices with a comprehensive coverage model, protocol checkers, and an extensive test suite.
  • More details are available on the DisplayPort Verification IP product page, Simulation VIP pages.
  • If you have any queries, feel free to contact us at talk_to_vip_expert@cadence.com




f

Use Verisium SimAI to Accelerate Verification Closure with Big Compute Savings

Verisium SimAI App harnesses the power of machine learning technology with the Cadence Xcelium Logic Simulator - the ultimate breakthrough in accelerating verification closure. It builds models from regressions run in the Xcelium simulator, enabling the generation of new regressions with specific targets. The Verisium SimAI app also features cousin bug hunting, a unique capability that uses information from difficult-to-hit failures to expose cousin bugs. With these advanced machine learning techniques, Verisium SimAI offers the potential for a significant boost in productivity, promising an exciting future for our users.

Figure 1: Regression compression and coverage maximization with Verisium SimAI 

What can I do with Verisium SimAI?

You can exercise different use cases with Verisium SimAI as per your requirements. For some users, the goal might be regression compression and improving coverage regain. Coverage maximization and hitting new bins could be another goal. Other users may be interested in exposing hard-to-hit failures, bug hunting for difficult to find issues. Verisium SimAI allows users to take on any of these challenges to achieve the desired results.

Let's go into some more details of these use cases and scenarios where using SimAI can have a big positive impact.

  1. Using SimAI for Regression Compression and Coverage Regain

Unlock up to 10X compute savings with SimAI!

Verisium SimAI can be used to compress regressions and regain coverage. This flow involves setting up your regression environment for SimAI, running your random regressions with coverage and randomization data followed by training, and finally, synthesizing and running the SimAI-generated compressed regressions. The synthesized regression may prune tests that do not help meet the goal and add more runs for the most relevant tests, as well as add run-specific constraints. This flow can also be used to target specific areas like areas involving a high code churn or high complexity.

You can check out the details of this flow with illustrative examples in the following Rapid Adoption Kits (RAK) available on the Cadence Learning and Support Portal (Cadence customer credentials needed):

 

  1. Using SimAI for Coverage Maximization and Targeting coverage holes

Reduce your Functional Coverage Holes by up to 40% using SimAI!

Verisium SimAI can be used for iterative coverage maximization. This is most effective when regressions are largely saturated, and SimAI will explicitly try to hit uncovered bins, which may be hard-to-hit (but not impossible) coverage holes. This is achieved using iterative learning technology where with each iteration, SimAI does some exploration and determines how well it performed. This technique can also be used for bug hunting by using holes as targets of interest.

See more details on the Cadence Learning and Support Portal:

 

  1. Using SimAI for Bug Hunting

Discover and fix bugs faster using SimAI!

Verisium SimAI has a new bug hunting flow which can be used to target the goal of exposing hard-to-hit failure conditions. This is achieved using an iterative framework and by targeting failures or rare bins. The goal to target failures is best exercised when the overall failure rate is typically low (below 5%). Iterative learning can be used to improve the ability to target specific areas. Use the SimAI bug hunting use case to target rare events, low hit coverage bins, and low hit failure signatures.

See more details on the Cadence Learning and Support Portal:

Unlock compute savings, reduce your functional coverage holes, and discover and fix bugs faster with the power of machine learning technology now enabled by Verisium SimAI!

Please keep visiting  https://support.cadence.com/raks to download new RAKs as they become available.

Please note that you will need the Cadence customer credentials to log on to the Cadence Online  Support  https://support.cadence.com/, your 24/7 partner for getting help in resolving issues related to Cadence software or learning Cadence tools and technologies.

Happy Learning!




f

Flow Control Credit Updates in PCIe 6.1 ECN

As technology continues to evolve at a rapid pace, the importance of robust and efficient interconnect standards cannot be overstated. Peripheral Component Interconnect Express (PCIe) has been a cornerstone in high-speed data transfer, enabling seamless communication between various hardware components.   

With the advent of PCIe 6.1 ECN, a significant advancement in speed and efficiency, ensuring the accuracy and reliability of its operations is paramount. One critical aspect of this is the verification of shared credit updates. For detailed understanding on Shared Credit, please refer Understanding PCIe 6.0 Shared Flow Control. 

In this blog, we will discuss why this verification is essential and what it entails.  

Introduction 

PCIe 6.1 ECN brings numerous advancements over earlier versions, such as increased bandwidth and faster data transfer speeds.   

A crucial mechanism for efficient data transmission in PCIe 6.0 is the credit-based flow control system. In this system, devices monitor credits, representing the buffer capacity available for incoming data.   

When a device transmits data, it uses credits, which are replenished or adjusted once the data is received and processed. This system ensures that the sender does not overload the receiver.  

Given the critical role of shared credit updates in maintaining the integrity and efficiency of data transfers, verification of these updates is crucial.  Proper management of credit updates is essential to ensure data integrity, as any discrepancies can lead to data loss, corruption, or system crashes.   

Verification also guarantees efficient resource allocation, preventing scenarios where some components are starved of credit while others have an excess, thus avoiding inefficiencies.  Credit inefficiencies pose issues in low power negotiations by preventing devices from entering low power states. Additionally, verification involves checking for proper error handling mechanisms, ensuring that the system can recover gracefully from errors in credit updates and maintain overall stability.   

PCIe 6.1 ECN Flow Control Optimizations Over PCIe 6.0

PCIe 6.1 ECN builds on the FLIT-based architecture introduced in PCIe 6.0, further optimizing flow control mechanisms to handle increased data rates and improved efficiency.  PCIe 6.1 ECN introduced refinements in credit management, making the allocation and advertisement of credits more precise, which helps in reducing bottlenecks and improving data flow efficiency.  Enhancements in flow control protocols ensure better management of buffer spaces and more efficient credit allocation. These enhancements are designed to handle the increased data rates and throughput demands of next-generation applications, ensuring robust and efficient data flow across PCIe devices.  

Below are some major updates: 

  1. There have been improvements in error detection and correction mechanisms in PCIe 6.1 ECN to enhance flow control reliability by ensuring that corrupted data packets are detected and handled appropriately without disrupting the flow of valid packets.  
  2. The merged credit system, which was a key feature introduced int PCIe 6.0 to simplify and optimize credit management, was further enhanced in PCIe 6.1 ECN to improve performance and efficiency.  
  3. PCIe 6.1 ECN introduced better algorithms for allocating and reclaiming merged credits to handle high data rates, introduced more robust error detection and correction mechanism reducing the degradation or system instability. 
  4. PCIe 6.1 ECN provided clear guidelines on how to implement the merged credit system correctly, helping developers to implement more reliable systems. For more details, please refer to Specifications section 2.6.1 Flow Control (FC) Rules.

Summary 

In summary, PCIe 6.0 is a complex protocol with many verification challenges. You must understand many new Spec changes and think about the robust verification plan for the new features and backward compatible tests impacted by new features. Cadence’s PCIe 6.0 Verification IP is fully compliant with the latest PCIe Express 6.0 specifications and provides an effective and efficient way to verify the components interfacing with the PCIe 6.0 interface. Cadence VIP for PCIe 6.0 provides exhaustive verification of PCIe-based IP and SoCs, and we are working with early adopter customers to speed up every verification stage.   

More Information

For more info on how Cadence PCIe Verification IP and Triple Check VIP enable users to confidently verify PCIe 6.0, see VIP for PCI Express, VIP for Compute Express Link  and TripleCheck for PCI Express  

See the PCI-SIG website for more details on PCIe in general and the different PCI standards.  

For more information on PCIe 6.0 new features, please visit PCIeLaneMarginPCIe6.0LaneMargin, and Demonstrating PCIe 6.0 Equalization Procedure.




f

Training Insights – Palladium Emulation Course for Beginner and Advanced Users

The Cadence Palladium Emulation Platform is a hardware system that implements the design, accelerating its execution and verification. Itoffers the highest performance and fastest bring-up times for pre-silicon validation of billion-gate designs, using a custom processor built by Cadence.

This Palladium Introduction course is based on the Palladium 23.03 ISR4 version and covers the following modules:

  • Introduction
  • Palladium flow
  • Running a design on the Palladium system

This course starts with an “Introduction” module that explains Palladium and other verification platforms to show its place in the big picture. It also compares Palladium with Protium and simulation and discusses its usage and limitations.

The “Palladium Flow” module includes two stages at a high level, which are Compile and Run. Then, it covers these stages in detail. First, it covers the ICE compile flow and IXCOM compile flow steps in detail. Then it explains Run, which is common for both ICE and IXCOM modes.

The third module, “Running Design on the Palladium System,” covers all the items required for running your design on the Palladium system, including:

  • Software stack requirements
  • Basic concepts required to understand the flow
  • Compute machine requirements

In addition, this course contains labs for both the ICE and IXCOM flows with detailed steps to exercise the features provided by the Palladium system. The lab explains a practical example of multiple counters and exercising their signals for force, monitor, and deposit features, along with frequency calculation using a real-time clock. The course is available on the Cadence support page:

There is also a Digital Badge available. You will find the Badge exam opportunity when you enroll in the Online training or after you have taken the training as "live" training.

For questions and inquiries, or issues with registration, reach out to us at Cadence Training. Want to stay up to date on webinars and courses? Subscribe to Cadence Training emails. To view our complete training offerings, visit the Cadence Training website.

Related Training Bytes

Related Courses

Related Blogs




f

DDR5 UDIMM Evolution to Clock Buffered DIMMs (CUDIMM)

DDR5 is the latest generation of PCDDR memory that is used in a wide range of application like data centers, Laptops and personal computers, autonomous driving systems, servers, cloud computing, and gaming are now increasingly being used for AI applications with advances in memory bandwidth and density to allow DDR5 DIMMs (Dual Inline Memory Modules) to support densities higher then 256 GB per DIMM card. The highest speed DDR5 SDRAM devices can support data rates of up to 8800 MTps.

DDR5 SO-DIMMs and UDIMMs

One of the most recognized uses of PCDDR is with client devices like laptops and personal computers. These client devices mostly use two types of DDR5 DIMMs called SO-DIMM (Small Outline Dual Inline Memory Module) and UDIMM (Unbuffered Dual Inline Memory Module).

These types of DIMMs have no signal regeneration or buffering (which, for example, the Registering Clock Driver or the RCD does for clocks/command/control signals for a registered DIMMs). A typical 2-Rank UDIMM with x8 DDR5 SDRAM components has 8 or 10 components per rank depending on the system ECC (Error Correction Code) memory being part of the DIMM.

Why DDR5 Clock Buffer and CUDIMM?

Clocks are one of the most important signals for synchronous devices, and DDR5 SDRAMs are no exception. The host is responsible for the fanout to all the DRAM input ports, such as clocks for UDIMMs. Driving of all these DRAM clocks can put quite a bit of load on the host output drivers, thus affecting the signal quality, which can result in unexpected memory errors. This issue gets amplified when operating at the higher clock and data rates where the clock signals transition from one logic value to the next over a very short time. To solve these signal integrity issues with DRAM clocks, JEDEC has come up with a new type of DDR5 DIMM component that is called DDR5 clock buffer. Clock buffers can be used for both DDR5 SO-DIMMs and DDR5 UDIMMs. DDR5 UDIMMs that include a clock buffer component as part of the DIMM card are called DDR5 CUDIMMs (Clock Buffered UDIMMs).

DDR5 Clock Buffer Overview

DDR5 Clock Buffer is a simple logic device that takes in two sets of input clock pins and drives two sets of clock pins as output per channel. The clock buffer device can operate in three types of clock modes: -

  • PLL bypass mode: In this mode, the clock buffer just passes on the input clocks to output without any kind of signal buffering. The PLL bypass mode enabled CUDIMM devices behave like traditional UDIMMs without any buffering of the clocks. This is why it’s also referred to as legacy mode. Recommended CUDIMM operating speeds in PLL bypass mode are typically limited to 3000 MHz.
  • Single PLL mode: In the single PLL Mode, the clock buffer device will use a Phase Lock Loop (PLL) for the regeneration of the incoming host clock to create a better-quality clock that is sent to the DRAMs. However, since there is only one PLL that is used in this mode, both sub channel output clocks will be driven based on only one set of input clocks with the other set of input clocks remaining unused.
  • Dual PLL mode: In this mode, the clock buffer will use two PLLs to independently generate each sub channel output clock based on each set of incoming host clocks. The second set of PLL can be turned on or off on the fly if needed to save power.

Beyond the clock modes, clock buffers provide additional flexibility to the system designers with register-controlled additional signal delays, optional output clock enable/disable per bit feature, drive strength and termination choices, etc. All DDR5 clock buffer device control word registers are accessible via DDR5 DIMM sideband.

Cadence VIPs offers a compressive memory subsystem solution that includes memory models for DDR5 SDRAM, DDR5 RCD, DDR5 DB, DDR5 clock buffer, all types of DDR5 DIMMs, including the DDR5 CUDIMMs, DFI Memory Controller/PHY VIPs, and a system VIP compliant to JEDEC specifications defined for each of those devices along with latest DFI Specification.

More information on Cadence DDR5 DIMM VIP is available at the Cadence VIP Memory Models website.




f

Jasper Formal Fundamentals 2403 Course for Starting Formal Verification

The course "Jasper Formal Fundamentals v24.03" introduces formal analysis to those who want to use formal analysis for design or verification. 

To optimally benefit from this course, you must already have sufficient knowledge of the System Verilog assertions to be capable of writing properties for formal verification. Hence, this training provides a module on formal analysis to help cover this essential background. 

In this course, you will learn how to code efficient SVA Properties for formal analysis, understand formal complexity and how to overcome it, and learn the basics of formal coverage.

After completing this course, you will be able to:

  • Define reusable, functionally correct SVA properties that are efficient for formal tools. These shall use abstract auxiliary code to simplify descriptions, make code maintenance easier, reduce debug time, and reduce tool-proof runtime.
  • Set up, run, and analyze results from formal analysis.
  • Identify designs upon which formal is likely to be successful while understanding formal complexity issues and how to identify and overcome them.
  • Use a systematic property development process to approach a completely new verification problem.
  • Understand the basics of formal coverage.

 The most recently updated release includes new modules on:

  • "Basic complexity handling" which discusses the complexity in formal and how to identify and handle them.
  • "Complexity reduction methods” which discusses the complexity reduction methods and which is suitable for which type of complexity problem.
  • “Coverage in formal” which discusses the basics of coverage in formal verification and how coverage can be used in formal.   

Take this course to learn the basics of formal verification. 

What's Next? 

You can check out the complete training: Jasper Formal Fundamentals. There is a free online version of the training available 24/7 for all customers with a Cadence Learning and Support Portal account. If you are interested in an instructor-led version of the training, please contact Cadence Training. And don't forget to obtain your digital badge after completing the training!

You can also check Jasper University page for more materials on formal analysis and Jasper apps. 

Related Trainings 

Jasper Formal Expert Training Course | Cadence

Verilog Language and Application Training Course | Cadence

SystemVerilog for Design and Verification Training Course | Cadence

SystemVerilog Assertions Training Course | Cadence

Related Training Bytes 

Jasper Formal Property Verification (FPV) App: Basic Usage Demo (Video)

Jasper Formal Methodology playlist

Related Training Blogs

It’s the Digital Era; Why Not Showcase Your Brand Through a Digital Badge!

Training Insights: Introducing the C++ Course for All Your C++ Learning Needs!

Training Insights: Reaching Your Verification Closure Using Verisium Manager

Training Insights - Free Online Courses on Cadence Learning and Support Portal




f

Partial Header Encryption in Integrity and Data Encryption for PCIe

Cadence PCIe/CXL VIP support for Partial Header Encryption in Integrity and Data Encryption.(read more)




f

Unveiling the Capabilities of Verisium Manager for Optimized Operations

In SoC development, the verification cycle is a crucial phase that ensures products meet their specifications and function correctly. However, the complexity of modern SoC projects, with their constant data flow, multiple validation teams working in parallel, and tight schedules, presents significant challenges. This article explores these challenges and introduces Verisium Manager as a solution that embodies the 'One Tool Fits All' concept. This means that Verisium Manager is designed to handle all aspects of the verification process for SoC development, from planning to coverage analysis to regression testing, thereby addressing the complex needs of SoC verification.

The Hurdles in Traditional Validation Cycles

 A typical validation process involves planning, coverage analysis, and regression testing. This complexity is compounded by using separate tools for each activity, leading to multiple control environments, APIs, and databases, not to mention the array of tool owners. Such fragmentation results in constant data transfer and translation between systems, from the planning tool to the coverage analysis tool and then to the regression testing tool. This continuous movement of data causes delays, system instability, poor user experiences, and, ultimately, a dip in the quality of the validation process.

The use of multiple platforms leads to inefficiency and reduced productivity. What's needed is a unified system that can streamline the workflow, simplify the verification process, and enhance its effectiveness.

Envisioning the Ideal Solution: Verisium Manager

 The cornerstone of an efficient validation cycle is integration and simplicity. The ideal solution is a singular platform that consolidates planning, coverage analysis, and regression management into one smooth, unified process. Verisium Manager emerges as this much-needed solution, encompassing all the functionalities necessary to streamline the validation process. Its comprehensive nature instills confidence in its ability to handle all aspects of the verification cycle. It can be fully customized to address and enforce any validation methodology and can facilitate smooth integration into any customer environment.

Features that stand out in Verisium Manager include: 

  • Unified Workflow: It acts as a single cockpit from which all activities are orchestrated, ensuring the validation teams' work is uninterrupted and seamlessly integrated.
  • Customization and Integration: Verisium Manager supports customizing test-plan structures and mapping results per project, ensuring a perfect fit for various project requirements. Its ability to smoothly integrate into the project's environment and compute platforms is unparalleled.
  • Support for Continuous Updates and Migration: The tool accommodates constant updates to project data and supports the migration of legacy data, ensuring that no historical data is lost in the transition to a new system.

Addressing Project-Specific Needs

 Verisium Manager recognizes diversity in different projects and offers project-specific solutions, including:

 Enforcing Project Test-Plan Structures and Attributes: It supports and enforces each project's unique test-plan structure and mapping guidelines.

  • Unified Data Views and Measurements: Verisium Manager promotes a unified view of data across all teams and enforces unified measurements, ensuring consistency and clarity in the validation process.
  • Enabling Project-Specific Actions and Integrations: The tool is designed to support project-specific actions directly from its graphical user interface and allows for smooth integration with in-house databases, dashboards, and the project execution stack.

Verisium Manager is the epitome of efficiency in software/hardware validation. Its differentiating features, such as support for customization, unified data view, and comprehensive coverage and regression requirements, make it an indispensable tool for any validation team looking to elevate their workflow.




f

A Brief on Message Bus Interface in PIPE

PHY Interface for the PCI Express (PCIe), SATA, USB, DisplayPort, and USB4 Architectures (PIPE) enables the development of the Physical Layer (PHY) and Media Access Layer (MAC) design separately, providing a standard communication interface between these two components in the system.

In recent years, the PIPE interface specification has incorporated many enhancements to support new features and advancements happening in the supported protocols. As the supported features increase, so does the count of signals on PIPE interface. To address the issue of increasing signal count, the message bus interface was introduced in PIPE 4.4 and utilized for PCIe lane margining at the receiver and elastic buffer depth control.

In PIPE 5.0, all the legacy PIPE signals without critical timing requirements were mapped into message bus registers so that their associated functionality could be accessed via the message bus interface instead of implementing dedicated signals. It was decided that any new feature added in the new version of PIPE specification will be available only via message bus accesses unless they have critical timing requirements that need dedicated signals.

Message Bus Interface

The message bus interface provides a way to initiate and participate in non-latency-sensitive PIPE operations using a small number of wires. It also enables future PIPE operations to be added without adding additional wires. The use of this interface requires the device to be in a power state with PCLK running.

Control and status bits used for PIPE operations are mapped into 8-bit registers that are hosted in 12-bit address spaces in the PHY and the MAC. The registers are accessed using read-and-write commands driven over the signals M2P_MessageBus[7:0] and P2M_MessageBus[7:0]. These signals are synchronous with the PCLK and are reset with Reset#.

Message Bus Interface Commands

The 4-bit commands are used for accessing the PIPE registers across the message bus. A transaction consists of a command and any associated address and data.

All the following are time multiplexed over the bus from MAC and PHY:

  1. Commands (write_uncommitted, write_committed, read, read completion, write_ack)
  2. 12-bit address used for all types and read and writes
  3. 8-bit data, either read or written

There can be cases where multiple PIPE interface signals can change on the same PCLK. To address such cases, the concept of write_uncommitted and write_committed is introduced.

The uncommitted write should be saved into a write buffer, and its associated data values are updated into the relevant PIPE register at a future time when a write_committed is received, taking effect during the same PCLK cycle. Once a write_committed is sent, no new writes, whether committed or uncommitted, and any read command may be sent until a write_ack is received. Also, it is allowed to send NOP commands between write uncommitted and write committed. 

A simple timing demonstration of message bus:

Message Address Space

MAC and PHY each implement unique 12-bit address spaces. These address spaces will host registers associated with the PIPE operations. MAC accesses PHY registers using M2P_MessageBus[7:0], and PHY accesses the MAC registers using the M2P_MessageBus[7:0].

The MAC and PHY access specific bits in the registers to: initiate operations, Initiate handshakes, and Indicate status.

Each 12-bit address space is divided into four main regions: the receiver address region, the transmitter address region, the common address region, and the vendor-specific address region.

Each register field has an attribute description of either level or 1-cycle assertion. When a level field is written, the value written is maintained by the hardware until the next write to that field or until a reset occurs. When a 1-cycle field is written to assert the value high, the hardware maintains the assertion for only a single cycle and then automatically resets the value to zero on the next cycle.

Cadence has a mature Verification IP solution for the verification of various aspects and topologies of PIPE PHY design. For more details, you may refer to the Simulation VIP for PIPE PHY | Cadence page, or you may send an email to support@cadence.com.




f

Deferrable Memory Write Usage and Verification Challenges

The application of real-time data processing or responsiveness is crucial, such as in high-performance computing, data centers, or applications requiring low-latency data transfers. It enables efficient use of PCIe bandwidth and resources by intelligently managing memory write operations based on system dynamics and workload priorities. By effectively leveraging Deferrable Memory Write [DMWr], Devices can achieve optimized performance and responsiveness, aligning with the evolving demands of modern computing applications.

What Is Deferrable Memory Write?

Deferrable Memory Write (DMWr) ECN introduced this new memory transaction type, which was later officially incorporated in PCIe 5.0 to CXL2.0. This enhanced type of memory transaction is Deferrable Memory Write [DMWr], which flows as another type of existing Read/Write memory transaction; the major difference of this Deferrable Memory Write, where the Requester attempts to write to a given location in Memory Space using the non-posted DMWr TLP Type, it Postponing their completion of memory write transactions to improve overall system efficiency and performance, those memory write operation can be delay or deferred until other priority task complete.

The Deferrable Memory Write (DMWr) requires the Completer to return an acknowledgment to the Requester and provides a mechanism for the recipient to defer (temporarily refuse to service) the Request.

DMWr provides a mechanism for Endpoints and hosts to choose to carry out or defer incoming DMWr Requests. This mechanism can be used by Endpoints and Hosts to simplify the design of flow control, reduce latency, and improve throughput. The Deferrable Memory writes TLP format in Figure A.

 

(Fig A) Deferrable Memory writes TLP format.

Example Scenario

Here's how the DMWr works with a simplified example: Imagine a system with an endpoint device (Device A) and a host CPU (Device B). Device B wants to write data to Device A's memory, but due to varying reasons such as system bus congestion or prioritization of other transactions, Device A can defer the completion of the memory write request. Just follow these steps:

  1. Initiation of Memory Write: Device B initiates a memory write transaction to Device A. This involves sending the memory write request along with the data payload over the PCIe physical layer link.
  2. Acknowledgment and Deferral: Upon receiving the memory write request, Device A acknowledges the transaction but may decide to defer its completion. Device A sends an acknowledgment (ACK) back to Device B, indicating it has received the data and intends to complete the write operation but not immediately.
  3. Deferred Completion: Device A defers the completion of the memory write operation to a later, more opportune time. This deferral allows Device A to prioritize other transactions or optimize the use of system resources, such as memory bandwidth or processor availability.
  4. Completion and Response: At a later point, Device A completes the deferred memory write operation and sends a completion indication back to Device B. This completion typically includes any status updates or additional information related to the transaction.

Usage or Importance of DMWr

Deferrable Memory Write usage provides the improvement in the following aspects:

  • Reduced Latency: By deferring less critical memory write operations, more critical transactions can be processed with lower latency, improving overall system responsiveness.
  • Improved Efficiency: Optimizes the utilization of system resources such as memory bandwidth and CPU cycles, enhancing the efficiency of data transfers within the PCIe architecture.
  • Enhanced Performance: Allows devices to manage and prioritize transactions dynamically, potentially increasing overall system throughput and reducing contention.

Challenges in the Implementation of DMWr Transactions

The implementation of deferrable memory writes (DMWr) introduces several advancements and challenges in terms of usage and verification:

  1. Timing and Synchronization: DMWr allows transactions to be deferred, complicating timing requirements or completing them within acceptable timing windows to avoid protocol violations. Ensuring proper synchronization between devices becomes critical to prevent data loss or corruption.
  2. Protocol Compliance: Verification must ensure compliance with ECN PCIe 6.0 and CXL specifications regarding when and how DMWr transactions can be initiated and completed.
  3. Performance Optimization: While DMWr can improve overall system performance by reducing latency, verifying its impact on system performance and ensuring it meets expected benchmarks is crucial.
  4. Error Handling: Handling errors related to deferred transactions adds complexity. Verifying error detection and recovery mechanisms under various scenarios (e.g., timeout during deferral) is essential.

Verification Challenges of DMWr Transactions

The challenges to verifying the DMWr transaction consist of all checks with respect to Function, Timing, Protocol compliance, improvement, Error scenario, and security usage on purpose, as well as Data integrity at the PCIe and CXL.

  1. Functional Verification: Verifying the correct implementation of DMWr at both ends of the PCIe link (transmitter and receiver) to ensure proper functionality and adherence to specifications.
  2. Timing Verification: Validating timing constraints associated with deferring writes and ensuring transactions are completed within specified windows without violating protocol rules.
  3. Protocol Compliance Verification: Checking that DMWr transactions adhere to PCIe and CXL protocol rules, including ordering rules and any restrictions on deferral based on the transaction type.
  4. Performance Verification: Assessing the impact of DMWr on overall system performance, including latency reduction and bandwidth utilization, through simulation and testing.
  5. Error Scenario Verification: Creating and testing scenarios to verify error handling mechanisms related to DMWr, such as timeouts, retries, and recovery procedures.
  6. Security Considerations: Assessing potential security vulnerabilities related to DMWr, such as data integrity risks during deferred transactions or exposure to timing-based attacks.

Major verification challenges and approaches are timing and synchronization verification in the context of implementing deferrable memory writes (DMWr), which is crucial due to the inherent complexities introduced by deferred transactions. Here are the key issues and approaches to address them:

Timing and Synchronization Issues

  1. Transaction Completion Timing:
    • Issue: Ensuring deferred transactions are completed within the specified time window without violating protocol timing constraints.
    • Approach: Design an internal timer and checker to model worst-case scenarios where transactions are deferred and verify that they are complete within allowable latency limits. This involves simulating various traffic loads and conditions to assess timing under different scenarios.
  2. Ordering and Dependencies:
    • Issue: Verifying that transactions deferred using DMWr maintain the correct ordering and dependencies relative to non-deferred transactions.
    • Approach: Implement test scenarios that include mixed traffic of DMWr and non-DMWr transactions. Verify through simulation or emulation that dependencies and ordering requirements are correctly maintained across the PCIe link.
  3. Interrupt Handling and Response Times:
    • Issue: Verify the handling of interrupts and ensure timely responses from devices involved in DMWr transactions.
    • Approach: Implement test cases that simulate interrupt generation during DMWr transactions. Measure and verify the response times to interrupts to ensure they meet system latency requirements.

In conclusion, while deferrable memory writes in PCIe and CXL offer significant performance benefits, their implementation and verification present several challenges related to timing, protocol compliance, performance optimization, and error handling. Addressing these challenges requires rigorous testing and testbench of traffic, advanced verification methodologies, and a thorough understanding of PCIe specifications and also the motivation behind introducing this Deferrable Write is effectively used in the CXL further. Outcomes of Deferrable Memory Write verify that the performance benefits of DMWr (reduced latency, improved throughput) are achieved without compromising timing integrity or violating protocol specifications.

In summary, PCIe and CXL are complex protocols with many verification challenges. You must understand many new Spec changes and consider the robust verification plan for the new features and backward compatible tests impacted by new features. Cadence's PCIe 6.0 Verification IP is fully compliant with the latest PCIe Express 6.0 specifications and provides an effective and efficient way to verify the components interfacing with the PCIe 6.0 interface. Cadence VIP for PCIe 6.0 provides exhaustive verification of PCIe-based IP and SoCs, and we are working with Early Adopter customers to speed up every verification stage.

More Information




f

Training Webinar: Protium X2: Using Save/Restart for Debugging

Cadence Protium prototyping platforms rapidly bring up an SoC or system prototype and provide a pre-silicon platform for early software development, SoC verification, system validation, and hardware regressions. In this Training W ebinar, we will explore debugging using Save/Restart on Protium X2 . This feature saves execution time and lets you focus on actual debugging. The system state can be saved before the bug appears and restartS directly from there without spending time in initial execution. We’ll cover key concepts and applications, explore Save/Restart performance metrics, and provide examples to help you understand the concepts. Agenda: The key concepts of debugging using save/restart Capabilities, limitations, and performance metrics Some examples to enable and use save/restart on the Protium X2 system Date and Time Thursday, November 7, 2024 07:00 PST San Jose / 10:00 EST New York / 15:00 GMT London / 16:00 CET Munich / 17:00 IST Jerusalem / 20:30 IST Bangalore / 23:00 CST Beijing REGISTER To register for this webinar, sign in with your Cadence Support account (email ID and password) to log in to the Learning and Support System*. Then select Enrol to register for the session. Once registered, you’ll receive a confirmation email containing all login details. A quick reminder: If you haven’t received a registration confirmation within 1 hour of registering, please check your spam folder and ensure your pop-up blockers are off and cookies are enabled. For issues with registration or other inquiries, reach out to eur_training_webinars@cadence.com . Want to See More Webinars? You can find recordings of all past webinars here Like This Topic? Take this opportunity and register for the free online course related to this webinar topic: Protium Introduction Training The course includes slides with audio and downloadable lab exercises designed to emphasize the topics covered in the lecture. There is also a Digital Badge available for the training. Want to share this and other great Cadence learning opportunities with someone else? Tell them to subscribe . Hungry for Training? Choose the Cadence Training Menu that’s right for you. To view our complete training offerings, visit the Cadence Training website . Related Courses Protium Introduction Training Course | Cadence Palladium Introduction Training Course | Cadence Related Blogs Training Insights – A New Free Online Course on the Protium System for Beginner and Advanced Users Training Insights – Palladium Emulation Course for Beginner and Advanced Users Related Training Bytes Protium Flow Steps for Running Design on Protium System ICE and IXCOM mode comparison ICE compile flow IXCOM compile flow PATH settings for using Protium System Please see the course learning maps for a visual representation of courses and course relationships. Regional course catalogs may be viewed here




f

Training Webinar: Fast Track RTL Debug with the Verisium Debug Python App Store

As a verification engineer, you’re surely looking for ways to automate the debugging process. Have you developed your own scripts to ease specific debugging steps that tools don’t offer? Working with scripts locally and manually is challenging—so is reusing and organizing them. What if there was a way to create your own app with the required functionality and register it with the tool? The answer to that question is “Yes!” The Verisium Debug Python App Store lets you instantly add additional features and capabilities to your Verisium Debug Application using Python Apps that interact with Verisium Debug via the Python API. Join me, Principal Education Application Engineer Bhairava Prasad, for this Training Webinar and discover the Verisium Debug Python App Store. The app store allows you to search for existing apps, learn about them, install or uninstall them, and even customize existing apps. Date and Time Wednesday, November 20, 2024 07:00 PST San Jose / 10:00 EST New York / 15:00 GMT London / 16:00 CET Munich / 17:00 IST Jerusalem / 20:30 IST Bangalore / 23:00 CST Beijing REGISTER To register for this webinar, sign in with your Cadence Support account (email ID and password) to log in to the Learning and Support System*. Then select Enroll to register for the session. Once registered, you’ll receive a confirmation email containing all login details. A quick reminder: If you haven’t received a registration confirmation within one hour of registering, please check your spam folder and ensure your pop-up blockers are off and cookies are enabled. For issues with registration or other inquiries, reach out to eur_training_webinars@cadence.com . Like this topic? Take this opportunity and register for the free online course related to this webinar topic: Verisium Debug Training To view our complete training offerings, visit the Cadence Training website Want to share this and other great Cadence learning opportunities with someone else? Tell them to subscribe . Hungry for Training? Choose the Cadence Training Menu that’s right for you. Related Courses Xcelium Simulator Training Course | Cadence Related Blogs Unveiling the Capabilities of Verisium Manager for Optimized Operations - Verification - Cadence Blogs - Cadence Community Verisium SimAI: SoC Verification with Unprecedented Coverage Maximization - Corporate News - Cadence Blogs - Cadence Community Verisium SimAI: Maximizing Coverage, Minimizing Bugs, Unlocking Peak Throughput - Verification - Cadence Blogs - Cadence Community Related Training Bytes Introducing Verisium Debug (Video) (cadence.com) Introduction to UVM Debug of Verisium Debug (Video) (cadence.com) Verisium Debug Customized Apps with Python API Please see course learning maps a visual representation of courses and course relationships. Regional course catalogs may be viewed here . *If you don’t have a Cadence Support account, go to Cadence User Registration and complete the requested information. Or visit Registration Help .




f

Cadence Fem.AI Summit: A Journey of Inspiration

This year, the Cadence Giving Foundation (CGF) launched Fem.AI to achieve a more inclusive tech sector, and the inaugural Fem.AI Summit that took place on October 1 was a luminary in a world where technology is evolving at an unprecedented pace. The summit not only excelled in its mission to enlighten, empower, and mobilize stakeholders across various industries on the issue of gender disparity in high tech and AI, but was a celebration of innovation, diversity, and empowerment. As we reflect on the moments that made the summit unforgettable, it's clear that the event was more than just a meeting of minds—it was a movement for change! Shaping Tomorrow Together Cadence’s president and CEO, Anirudh Devgan, stated, “Women’s talent and perspectives are crucial to shaping the future of AI.” Devgan’s words epitomized the driving force behind the first-ever Fem.AI Summit which brought together innovators, educators, business leadership, and investors across industries to create an ecosystem that ensures women can fully participate in the AI revolution and burgeoning AI economy. The energy of pioneers ready to collectively disrupt the status quo filled the air, and as the day-long summit began, it became clear that we were part of something truly groundbreaking. The event's lineup of speakers held discussions that went beyond the technical aspects of AI, emphasizing the vital importance of diversity in technology. Such insights were lent by leading voices from MIT, Stanford, and UC Berkeley, who set the stage for inspiring discussions with speakers like Dr. Joy Buolamwini, Founder of the Algorithmic Justice League, and Reshma Saujani, Founder and CEO of Moms First and Girls Who Code. Included in this lineup of leading figures was Dr. Chelsea Clinton, Vice Chair of the Clinton Foundation, who left us with her hopes for the future of women in AI: “I’m hoping because of company-wide commitments like what we’re experiencing here today thanks to Cadence, that the people who will be part of designing [future technologies] will have a different group of people around the proverbial table or the computer screens doing that… and that women will be more integral into the conceptualization and then the actualization of AI-driven enterprises.” The hopes and visions for women in AI cannot manifest in a vacuum, they must be achieved with the support of individuals and systems from education all the way to the upper echelons of leadership. It is with this understanding, that Fem.AI is committed to investing in women at every stage of their STEM journey. Breaking Barriers It is with this ideal that we were honored to hear from women breaking through barriers of gender, race, and class in achieving pinnacles of success in areas of science and technology. Dr. Sarah H. Chen, Postdoctoral Researcher at Stanford and Thriving Stars Scholar at MIT, Niki Karanikola, Machine Learning Engineer and Break Through Tech AI Scholar at MIT, and Katya Echazarreta, NASA’s first Mexican Astronaut, showcased the resilience and determination that drive progress within and beyond our industry. Through their stories of persevering despite all odds, we were reminded that supporting students in STEM can create generational change with impacts beyond the realms of AI and technology. The final speaker at the Cadence Fem.AI Summit, the trailblazing Brandi Chastain, Founder of Bay FC, World Cup Champion, and Olympic Gold Medalist, left us with a powerful reminder that when faced with this opportunity: “Our purpose needs to be intentional” especially in building the future of technology and AI where “diversity is not something to be afraid of, but something to be embraced.” Echoing this sentiment, summit attendees left the event reminded of the crucial role we collectively play in ensuring women are part of this tech revolution. Moving Forward While the summit may have concluded, its impact will continue through individuals, companies, and communities aspiring to achieve an equitable tech sector. This is just the start, and we must take collective action now. We hope that you will join Cadence to ensure that we clear the path and catalyze women's role in the AI revolution! Meet Our Partners Our partners are making Fem.AI’s vision a reality through their important work advancing women in technology, including fostering STEM excellence in higher education, launching STEM careers, and achieving gender diversity in leadership. Learn more about the important work of each of our partners by visiting their pages: Break Through Tech Last Mile Education Fund Fast Forward Generation VC Include Global Semiconductor Alliance Join the Fem.AI Alliance Joining the Fem.AI Alliance signals that your company or institution is committed to evolving the AI workforce. By increasing the representation of women in AI, we aim to broaden the talent pool and the perspective so that AI represents us all. Through the Fem.AI Alliance, companies and institutions can share best practices, guidance, and inspiration. Since its launch, companies like the Equinix Foundation, NetApp, NVIDIA, Unity Technologies, and Workday have joined the Alliance in their commitment to Fem.AI’s work and mission. Visit Fem.AI to get involved today or contact Fem.AI@cadence.com .




f

Women in CFD with Vassiliki Moschou

In this edition of the Women in CFD series, we feature Vassiliki Moschou, aka Vicky, senior supervisor at BETA CAE, now part of Cadence. Her career journey serves as an inspiration for anyone who believes that studying in one field and working in another is less desirable. Vicky demonstrates how knowledge gained in one discipline can be effectively applied in another, often providing fresh and intriguing insights. Join us in this conversation to learn more about Vicky, her career path, and her advice for those considering a career in a field different from their studies. Tell us something about yourself. I've lived all my 41 years in the vibrant city of Thessaloniki, Greece. I’m married to my high school sweetheart, and together we're raising two incredible daughters who are 11 and almost 8 years old. These girls are absolutely the center of my world, and every day with them feels like a gift. My entire life, including where I have built my career and family, is deeply rooted in Thessaloniki. It's not just where I am from; it's a big part of who I am. Could you share your educational background and how you first became interested in computational fluid dynamics (CFD)? In 2001, I started my academic journey at the Computer Science Department of Aristotle University of Thessaloniki , where I focused on studying signal processing and artificial intelligence. This field fascinated me, and I pursued a master’s degree in the same area to further my expertise. Concurrently, I was involved in European research programs on signal/audio processing and machine learning methodologies. It became evident early on that my career would revolve around software engineering, a path I was fully prepared to pursue. However, everything took a turn when I joined BETA CAE in 2008. It was there that I was introduced to the field of CFD, which was completely unfamiliar to me at the time. This presented a new challenge that I eagerly accepted. I received support from all my colleagues, but I was primarily mentored by two brilliant and dedicated engineers, Michael Giannakidis and Vangelis Skaperdas , who introduced me to the world of CFD. Over time, what was once an unknown territory for me has become my passion. My journey through CFD has been a significant part of my professional growth. In my 30s, I pursued and completed a PhD in systems physiology in collaboration with the Medical and Computer Science Departments of Aristotle University of Thessaloniki. Our research focused on examining the EGF-activated MAPK pathway (often associated with cancer) from the perspective of complex self-organizing systems. Using graph theory, signal processing, and machine learning, we extracted information from the signals observed in this dynamic, distributed biological system to target novel drug development. What are the different positions you have held within the company, and what responsibilities do you currently hold? I started my career as a junior engineer at BETA CAE (now Cadence). It was a role that plunged me deep into the fascinating worlds of software and CFD, a crucial time of my career filled with learning and growth. My hard work and dedication didn't go unnoticed, and after a few years, I was promoted. That promotion was the first step on a career ladder that I've been ascending ever since. Now, I'm in the position of a senior supervisor. Though my job now involves a wide range of managerial tasks, I'm still deeply passionate about the technical side of things. I love writing code and working through the complexities of our projects, merging my leadership responsibilities with my enthusiasm for the technical facets of our work. What would you be doing if not working in CFD? Had my career taken a different trajectory, I envision myself in a role deeply embedded in human connections—perhaps as the owner of a quaint bakery or a cozy hotel, a teacher, or even venturing into human resources. There's a certain allure in careers that foster direct engagement with people, creating experiences and memories. In fact, I have an inherent desire to connect and communicate with people, aspects that are fundamentally different yet equally fulfilling as my current career. What are some of your favorite pastimes and hobbies? Family is at the center of my leisure time. We love taking short trips to the village, hanging out with our friends, and connecting. Our activities range from solving puzzles in escape rooms to passionately cheering at basketball games, especially since my older daughter has taken up the sport. But beyond these activities, being a mother is my most cherished pastime. The moments I share with my daughters, the lessons we learn together, and the joy we find in everyday adventures are what I hold dear. What are your thoughts on women in technical fields? The landscape for women in technical fields is gradually transforming, a change I observe with optimism and hope. In Greece, the increasing presence of women in engineering is a positive sign. In Cadence specifically, the representation of women is high compared to other tech companies. As a mother to two daughters, I am acutely aware of the importance of being a role model to them. It's crucial to demonstrate that aspirations should not be limited by gender and that the technical field is as much a place for women as it is for men. Encouraging this mindset is vital for the progress of our society and for the empowerment of the next generation of women in technology. Advice from Vicky for those considering a career in a field different from their studies: Learning is a lifelong journey. Embrace every challenge as an opportunity to grow and learn something new. Stay curious and adaptable to navigate the ever-evolving landscape of technology. Being labeled an 'expert' is less important than the willingness to learn and adapt. Finding happiness in your work can lead to natural success. In the epoch of artificial intelligence, train the most powerful neural network: your brain. At Cadence, our commitment is towards establishing an inclusive workspace where women feel empowered to achieve their professional best. Anchored by our One Cadence—One Team ethos, we take pride in fostering a community where our driven, devoted, and skilled women employees excel, making exceptional contributions to our customers, communities, and one another. Are you just like Vicky, venturing beyond your academic background, and considering a career in a different domain while being surrounded by an encouraging and uplifting atmosphere? Then, you won't want to miss exploring career opportunities at Cadence—celebrated as 'A Great Place for Women to Work'! Click the button below to discover your next adventure! Learn more about Cadence Fem.AI Alliance, which aims to lead the gender equity revolution in the AI workforce.




f

Versatile Use Case for DDR5 DIMM Discrete Component Memory Models

DDR5 DIMM Architectures The DDR5 generation of Double Data Rate DRAM memories has experienced rapid adoption in recent years. In particular, the JEDEC-defined DDR5 Dual Inline Memory Module (DIMM) cards have become a mainstay for systems looking for high-density, high-bandwidth, off-chip random access memory[1]. Within a short time, the DIMM architecture evolved from an interconnected hierarchy of only SDRAM memory devices (UDIMM[2]) to complex subsystems of interconnected components (RDIMM/LRDIMM/MRDIMM[3]). DIMM Designs and Popular Verification Use Cases The growing complexity of the DIMMs presented a challenge for pre-silicon verification engineers who could no longer simply validate against single DDR5 SDRAM memory models. They needed to consider how their designs would perform against DIMMs connected to each channel and operating at gigahertz clock speeds. To address this verification gap, Cadence developed DDR5 DIMM Memory Models that encapsulated all of the architectural complexities presented by real-world DIMMs based on a robust, easy-to-use, easy-to-debug, and easy-to-reconfigure methodology. This memory-subsystem-in-a-single-instance model has seen explosive adoption among the traditional IP Developer and SOC Integrator customers of Cadence Memory Models. The Cadence DIMM models act as a single unit with all of the relevant DIMM components instantiated and interconnected within, and with all AC/Timing parameters among the various components fully matched out-of-the-box, based on JEDEC specifications as well as datasheets of actual devices in the market. The typical use-case for the DIMM models has been where the DUT is a DDR5 Memory Controller + PHY IP stack, and the validation plan mandated compliance with the JEDEC standards and Memory Device vendor datasheets. Unique Use Case for the DIMM Discrete Component Models Although the Cadence DIMM models have enjoyed tremendous proliferation because of their cohesive implementation and unified user API, the actual DIMM Models are built on top of powerful, flexible discrete component models, each of which was designed to stand on its own as a complete SystemVerilog UVM-based VIP. All of these discrete component models exist in the Cadence VIP Catalog as standalone VIPs, complete with their own protocol compliance checking capabilities and their own configuration mappings comprehensively modeling individual AC/Timing parameters. Because of this deliberate design decision, the Cadence DIMM Discrete Component Models can support a unique use-case scenario. Some users seek to develop IC Designs for the various DIMM components. Such users need verification environments that can model the individual components of a DIMM and allow them the option to replace one or another component with their Component Design IP. They can then validate that their component design is fully compatible with the rest of the components on the DIMM and meets the integrity of the overall DIMM compliance with JEDEC standards or Memory Vendor datasheets. The Cadence Memory VIP portfolio today includes various examples that demonstrate how customers can create DIMM “wrappers” by selecting from among the available DIMM discrete component models and “stitching” them together to build their own custom testbench around their specific Component Design IP. A Solution for Unique Component Scenarios The Cadence DDR5 DIMM Memory Models and DIMM Discrete Component Models can provide users with a flexible approach to validating their specific component designs with a fully populated pre-silicon environment. Augmented Verification Capabilities When the DIMM “wrapper” model is augmented with the Cadence DFI VIP[4] that can simulate an MC+PHY stack and offers a SystemVerilog UVM test API to the verification engineer, the overall testbench transforms into a formidable pre-silicon validation vehicle. The DFI VIP is designed as a combination of an independent DFI MC VIP and a DFI PHY VIP connected to each other via the DFI Standard Interface and capable of operating seamlessly as a single unit. It presents a UVM Sequence API to the user into the DFI MC VIP with the Memory Interface of the PHY VIP connected to the DIMM “wrapper” model. With this testbench in hand, the user can then fully take advantage of the UVM Sequence Library that comes with the DFI VIP to enable deep validation of their Component Design inside the DIMM “wrapper” model. Verification Capabilities Further Enhanced A possible further enhancement comes with the potential addition of an instance of the Cadence DIMM Memory Model in a Passive Monitor mode at the DRAM Memory Interface. The DIMM Passive Monitor consumes the same configuration describing the DIMM “wrapper” in the testbench, and thus can act as a reference model for the DIMM wrapper. If the DIMM Passive Monitor responds successfully to accesses from the DFI VIP, but the DIMM wrapper does not, then it exposes potential bugs in the DUT Components or in the settings of their AC/Timing parameters inside the DIMM wrapper. Debuggability, Interface Visibility, and Protocol Compliance One of the key benefits of the DIMM Discrete Component Models that become manifest, whether in terms of the unique use-case scenario described here, or when working with the wholly unified DDR5 DIMM Memory Models, is the increased debuggability of the protocol functionality. The intentional separation of the discrete components of a DIMM allows the user to have full visibility of the memory traffic at every datapath landmark within a DIMM structure. For example, in modeling an LRDIMM or MRDIMM, the interface between the RCD component and the SDRAM components, the interface between the RCD component and the DB components, and the interface between the SDRAM components and the DB components—all are visible and accessible to the user. The user has full access to dump the values and states of the wire interconnects at these interfaces to the waveform viewer and thus can observe and correlate the activity against any protocol violations flagged in the trace logs by any one or more of the DIMM Discrete Component Models. Access to these interfaces is freely available when using the DIMM Discrete Component Models. On the unified DDR5 DIMM Memory Models, a feature called Debug Ports enables the same level of visibility into the individual interconnects amidst the SDRAM components, RCD components, and DB components. When combined with the Waveform Debugger[5] capability that comes built-in with the VIPs and Memory Models offered by Cadence and used with the Cadence Verisium Debug[6] tool, the enhanced debuggability becomes a powerful platform. With these debug accesses enabled, the user can pull out transaction streams, chip state and bank state streams, mode register streams, and error message streams all right next to their RTL signals in the same Verisium Debug waveform viewer window to debug failures all in one place. The Verisium Debug tool also parses all of the log files to probe and extract messages into a fully integrated Smart Log in a tabbed window fully hyperlinked to the waveform viewer, all at your fingertips. A Solution for Every Scenario Cadence's DDR5 DIMM Memory Models and DIMM Discrete Component Models , partnered with the Cadence DFI VIP, can provide users with a robust and flexible approach to validating their designs thoroughly and effectively in pre-silicon verification environments ahead of tapeout commitments. The solution offers unparalleled latitude in debuggability when the Debug Ports and Waveform Debugger functions of the Memory Models are switched on and boosted with the use of the Cadence Verisium Debug tool. [1] Shyam Sharma, DDR5 DIMM Design and Verification Considerations , 13 Jan 2023. [2] Shyam Sharma, DDR5 UDIMM Evolution to Clock Buffered DIMMs (CUDIMM) , 23 Sep 2024. [3] Kos Gitchev, DDR5 12.8Gbps MRDIMM IP: Powering the Future of AI, HPC, and Data Centers , 26 Aug 2024. [4] Chetan Shingala and Salehabibi Shaikh, How to Verify JEDEC DRAM Memory Controller, PHY, or Memory Device? , 29 Mar 2022. [5] Rahul Jha, Cadence Memory Models - The Gold Standard , 15 Apr 2024. [6] Manisha Pradhan, Accelerate Design Debugging Using Verisium Debug , 11 Jul 2023.




f

Redefining Hearing Aids with Cadence DSPs

Hearing is one of the most essential senses for engaging with the world. It enables us to converse, appreciate music, and remain alert to our surroundings. Hearing loss is a prevalent issue affecting millions of individuals globally and disconnecting them from a world where sound is vital to others and the environment. The World Health Organization (WHO) reports that over 5% of the global population requires hearing rehabilitation, a striking statistic highlighting this issue's pervasive nature. Technology has transformed audiology, evolving from simple ear trumpets to sophisticated modern hearing aids. This advancement began with the invention of the transistor, paving the way for devices that are fully wearable inside or behind the ear. Although hearing aids have been available for many years, historically, access to these critical devices has been insufficient, resulting in numerous individuals lacking the necessary support. However, recent advances in hearing aid technology promise improved acoustic experiences, employing modern techniques like binaural processing and neural networks. These innovations demand sophisticated architecture to balance high memory needs with low power consumption in a user-friendly design. Cadence is at the forefront of this technological evolution, offering tools and IP solutions that enhance the accessibility, efficiency, and impact of hearing aids, paving the way for a more inclusive future. This blog explores how Cadence's advanced DSPs are transforming hearing aid design and making them more accessible, efficient, and impactful. Hearing Aids: A Testament to Human Ingenuity The transition from analo g to digital technology in the late 20th century further transformed hearing aids, offering superior sound quality, customization, and the ability to connect to various electronic devices, thus enhancing the user experience markedly. Today's hearing aids are highly effective, versatile, and nearly invisible, a significant advancement from early attempts to address hearing loss. They also feature advanced noise cancellation and connectivity options, allowing users to integrate seamlessly into the digital world. This progression not only highlights the industry's commitment to improving user experience and accessibility but also offers a glimpse into a future where hearing loss is no longer a barrier. Challenges Despite advancements and sophistication, there are several challenges related to hearing aid design and adoption. Users demand smaller, more discreet devices that don't sacrifice performance. While the shift towards sleeker designs is aesthetically pleasing, it introduces substantial complexities in product design. Designers face the challenges of integrating essential components, such as batteries and peripherals, into increasingly compact spaces. Power consumption remains a critical concern, as these devices must remain operational throughout the day. Leveraging neural networks to enhance the signal-to-noise ratio (SNR) for better quality demands additional memory capacity. Consequently, there is a pressing need for flexible, low-power architectures that incorporate all necessary memory and peripherals without compromising the device’s compact size. Adopting AI for adjusting hearing aid volume to fit an individual's specific auditory requirements is a significant challenge and demands more memory and effort. Besides this, reliability and cost are significant challenges for manufacturers. Cadence's Role in Transforming Hearing Aids In hearing aid development, the capacity to evaluate the energy efficiency of SoCs across different frequencies in real time is crucial. These applications demand cohesive, energy-efficient solutions that can uphold high performance. The Cadence Tensilica HiFi and Fusion F1 DSP family emphasize minimal power usage while providing robust performance, ideally suited for a wide range of audio and voice applications. The Cadence Tensilica HiFi DSP family, a high-performance audio technology with AI acceleration and advanced DSP capability, offers feature-rich audio, speech, and imaging for wearables, automotive, home entertainment, digital assistants, and ASR. The Tensilica HiFi DSP family accelerates innovation with its comprehensive instruction set and supports fixed- and floating-point data types. Simplifying software development, it offers C/C++ programming, an auto-vectorizing compiler, and a rich DSP software library through the Cadence Tensilica Xplorer development environment. With the flexibility to customize and enhance performance through additional instructions and better I/O bandwidth, the Tensilica HiFi and Fusion DSP families offer a robust, low-energy audio solution compatible across an expansive software ecosystem for various applications and devices. Conclusion Technological advancements are driving hearing aid evolution; the future of hearing aids lies in further miniaturization and functionality enhancement. Cadence's ongoing innovations aim to improve signal processing and noise reduction, even in challenging environments. The integration of neural networks promises more apparent sound transmission and greater adaptability. Cadence is working on improving how these devices process signals and reduce noise and has initiated a collaborative venture with distinguished entities like GlobalFoundries (GF), Hoerzentrum Oldenburg gGmbH, and Leibniz University Hannover. This collaboration has borne fruit in the form of the industry's first binaural hearing aid system-on-chip (SoC) prototype, the Smart Hearing Aid Processor ( SmartHeAP ). Learn More Cadence, GlobalFoundries, Hoerzentrum Oldenburg and Leibniz University Hannover Collaborate to Advance Hearing Aid Technology Cadence Extends Battery Life and Improves User Experience for Next-Generation Hearables, Wearables and Always-On Devices Advancing the Future of Hearing Aids with Cadence Bluetooth LE Audio, Hearing Aids, and Mindtree




f

Lessons from the UMass Lowell Women’s Leadership Conference

This post was contributed by Liliko Uchida, application engineer at Cadence. Being a “Woman in STEM” is a phrase that has long been used to describe the holistic experience shared by thousands of women globally, yet it still makes us feel isolated. Partially due to the statistics of gender population in the STEM workforce and the remainder due to our own internal obstacles, being a woman in STEM continues to be a challenge. While many of us know the should-do’s and should-be’s of taking on this unique role objectively, we struggle to implement them. After all, our perseverance as engineers, mathematicians, businesswomen, programmers, and scientists is largely affected by subjectivity. The UMass Lowell Women’s Leadership Conference 2024 aimed to tackle this problem by uniting hundreds of women with shared experiences under one roof. Not only did the conference provide us with the knowledge necessary to persevere, but it also gave us the tools that will allow us to thrive and act upon the facts we already know. It is my hope that through this blog post, I can share some of my main takeaways from this special day. Be Confident This is one of the most palpable pieces of advice we always hear. Yet so many of us struggle to build this confidence because we don’t know how. Featured speaker Nicole Kalil defined confidence as “complete trust in oneself”.”One way to build this self-trust is by getting to know yourself on a deeper level. By creating a true inner connection, we begin to see ourselves as a whole instead of hyper-focusing on our shortcomings frequently illusioned by imposter syndrome. In one of the sessions, we were asked to introduce ourselves to our neighbors, not by what we do for work, but by who we are as a person. Even if this opportunity does not arise every day, this practice can be done simply by listing characteristics of yourself that define who you are. Who do you care for? How do you show them? What are your life goals oriented towards? How do you observe others’ behavior around you, and what does that say about how you make them feel? Getting to know you beneath the surface and allowing yourself to be seen for who you are is critical in building internal confidence. With practice, this self-reassurance will grow independent of external factors. Take Risks “Sometimes, you have to put your foot in the elevator” - Barb Vlacich, Keynote Speaker When opportunities arise, the only thing you can do to have a chance is to try. Without putting your foot in the elevator, the doors will close, becoming a missed opportunity. Similarly, several of the conference’s speakers also emphasized that the answer to every unasked question will always be a no. Even if you are not ready to full-send a negotiation, ask for a raise, or respectfully disagree with a co-worker’s opinion, start by getting comfortable asking uncomfortable questions. Just one discomfort a day will help in building an immunity to the anxiety that comes with taking risks, typically driven by our self-doubt. Another interesting point that stood out from the conference was the statistics of self-assessed qualifications between men and women. During the negotiation panel, it was revealed that men typically feel they only need 60% of the qualifications under a job description to apply, whereas women often feel they need close to 100%. These numbers alone demonstrate how the pure mental habits of men continue to funnel them into STEM and not women. The next time you seek a new opportunity, assess yourself based on the 60% and use it as a checklist threshold. If more women are able to pursue STEM careers using these numbers, the more likely we will begin to populate these roles. Build Your Genuine Network “ The essence of communication lies in the mutual exchange of ideas and emotions. And when the listener isn’t invested, it undermines the entire purpose of the conversation. Why are you having it anyway?” This is a quote from episode 186 of Julie Brown’s podcast This Sh!t Works called “The 5 Steps to Being an Active Listener”. Julie Brown is a Networking Coach, author, and podcast host who guided an energetic and candid conversation about networking and building a personal brand for women. Networking is often misunderstood as putting your name and qualifications out on the table for as many people to pick up your cards. While making these things known is important, they are not what nurtures effective connections. The key to cultivating your genuine network is to activate a sincere interest in the people you meet. Become the proactive receiver of the confidence exercise discussed above. When you meet someone new, what can you take away from them as a person, not an employee? By making people feel heard, even through the little conversations, you can begin to develop more meaningful connections that resonate. And, with practice, the sometimes inherent need to overcompensate by defining yourself with your resume will slowly fade. It was a wonderful opportunity to attend the UML Women’s Leadership Conference with four other inspiring Cadence women. Not only was the conference a motivating learning experience, but it was also a wonderful opportunity for us to bond together as women and feel supported by each other. The most eye-opening part of the day was seeing just how many women alike were sitting under the same roof. The conclusion of the event led me to feel proud to be an engineer, proud to be at Cadence, and most importantly, proud to be a woman. Learn more about life at Cadence .




f

Solutions to Maximize Data Center Performance Featured at OCP Global Summit 2024

The demand for higher compute performance, energy efficiency, and faster time-to-market drove the conversations at this year's Open Compute Project (OCP) Global Summit in San Jose, California. It was the scene of showcasing groundbreaking innovations, expert-led sessions, and networking opportunities to drive the future of data center technology. For those who didn't get to attend or stop by our booth, here's a recap of Cadence's comprehensive solutions that enable next-generation compute technology, AI data center design, analysis, and optimization. Optimized Data Center Design and Operations As the data center community increasingly faces demands for enhanced efficiency, thermal management, sustainability, and performance optimization, data center operators, IT managers, and executives are looking for solutions to these challenges. At the Cadence booth, attendees explored the Cadence Reality Digital Twin Platform and Celsius EC Solver. These technologies are pivotal in achieving high-performance standards for AI data centers, providing advanced digital twin modeling capabilities that redefine next-generation data center design and operation. The Celsius EC Solver demonstration showed how it solves challenging thermal and electronics cooling management problems with precision and speed. CadenceCONNECT: Take the Heat Out of Your AI Data Center Cadence hosted a networking reception on October 16 titled "Take the Heat Out of Your AI Data Center." In today's AI era, managing the heat generated by high-density computing environments is more critical than ever. This reception offered insights into current and emerging data center technologies, digital twin cooling strategies that deliver energy-saving operations, and a chance to engage with industry leaders, Cadence experts, and peers to explore the latest cooling, AI, and GPU acceleration advancements. Here's a recap: Researcher, author, and entrepreneur Dr. Jon Koomey highlighted the inefficiency of data centers in his talk "The Rise of Zombie Data Centers," noting that 20-30% of their capacity is stranded and unused. He advocated for organizational changes and technological solutions like digital twins to reduce wasted energy and improve computational effectiveness as AI deployments increase. In "A New Millennium in Multiphysics System Analysis," Cadence Corporate VP Ben Gu explained the company's significant strides in multiphysics system analysis, evolving from chip simulation to a broader application of computational software for simulating various physical systems, including entire data centers. He noted that the latest Cadence venture, a digital twin platform for data center optimization, opened the opportunity to use simulation technology to optimize the efficiency of data centers. Senior Software Engineering Group Director Albert Zeng highlighted the Cadence Reality DC suite's ability to transform data center operations through simulation, emphasizing its multi-phase engine for optimal thermal performance and the integration of AI capabilities for enhanced design and management. A panel discussion titled "Turning AI Factory Blueprints into Reality at the Speed of Light" featured industry experts from NVIDIA, Norman Wright Precision Environmental and Power, NV5, Switch Data Centers, and Cadence, who explored the evolving requirements and multidimensional challenges of AI factories, emphasizing the need for collaboration across the supply chain to achieve high-performing and sustainable data centers. Watch the highlights. Transforming Designs from Chips to Data Centers The OCP Global Summit 2024 has reaffirmed its status as a pivotal event for data center professionals seeking to stay at the forefront of technological advancements. Cadence's contributions, from groundbreaking digital twin technologies to innovative cooling strategies, have shed light on the path forward for efficient, sustainable data centers. For data center professionals, IT managers, and engineers, the insights gained at this summit are invaluable in navigating the challenges and opportunities presented by the burgeoning AI era. Partnering with Arm Arm Total Design Cadence is a member of the Arm Total Design program. At an invitation-only special Arm event, Cadence's VP of Research and Development, Lokesh Korlipara, delivered a presentation focusing on data center challenges and design solutions with Arm Neoverse Compute Subsystem (CSS). The session highlighted: Efficient integration of Arm Neoverse CSS into system on chips (SoCs) with pre-integrated connectivity IP Performance analysis and verification of the Neoverse CSS integration into the SoC through Cadence's System VIP verification suite and automated testbench creation, enhancing both quality and productivity Jumpstarting designs through Cadence's collaboration with Arm for 3D-IC system planning, chiplets, and interposers Design Services readiness and global scale to support and/or deliver the most demanding Arm Neoverse CSS-based SoC design projects Cadence Supports Arm CSS in Arm Booth During the event, Cadence conducted a demo in the Arm booth that showcased the Cadence System VIP verification suite. The demo highlighted automated testbench creation and performance analysis for integrating the Arm CSS into SoCs while enhancing verification quality and productivity. Summary Cadence offers data center solutions for designing everything from the compute and networking chips to the board, racks, data centers, and campuses. Stay connected with Cadence and other industry leaders to continue exploring the innovations set to redefine the future of data centers. Learn More Cadence Joins Arm Total Design Cadence Arm-Based Solutions Cadence Reality Digital Twin Platform




f

Randomization considerations for PCIe Integrity and Data Encryption Verification Challenges

Peripheral Component Interconnect Express (PCIe) is a high-speed interface standard widely used for connecting processors, memory, and peripherals. With the increasing reliance on PCIe to handle sensitive data and critical high-speed data transfer, ensuring data integrity and encryption during verification is the most essential goal. As we know, in the field of verification, randomization is a key technique that drives robust PCIe verification. It introduces unpredictability to simulate real-world conditions and uncover hidden bugs from the design. This blog examines the significance of randomization in PCIe IDE verification, focusing on how it ensures data integrity and encryption reliability, while also highlighting the unique challenges it presents. For more relevant details and understanding on PCIe IDE you can refer to Introducing PCIe's Integrity and Data Encryption Feature . The Importance of Data Integrity and Data Encryption in PCIe Devices Data Integrity : Ensures that the transmitted data arrives unchanged from source to destination. Even minor corruption in data packets can compromise system reliability, making integrity a critical aspect of PCIe verification. Data Encryption : Protects sensitive data from unauthorized access during transmission. Encryption in PCIe follows a standard to secure information while operating at high speeds. Maintaining both data integrity and data encryption at PCIe’s high-speed data transfer rate of 64GT/s in PCIe 6.0 and 128GT/s in PCIe 7.0 is essential for all end point devices. However, validating these mechanisms requires comprehensive testing and verification methodologies, which is where randomization plays a very crucial role. You can refer to Why IDE Security Technology for PCIe and CXL? for more details on this. Randomization in PCIe Verification Randomization refers to the generation of test scenarios with unpredictable inputs and conditions to expose corner cases. In PCIe verification, this technique helps us to ensure that all possible behaviors are tested, including rare or unexpected situations that could cause data corruption or encryption failures that may cause serious hindrances later. So, for PCIe IDE verification, we are considering the randomization that helps us verify behavior more efficiently. Randomization for Data Integrity Verification Here are some approaches of randomized verifications that mimic real-world traffic conditions, uncovering subtle integrity issues that might not surface in normal verification methods. 1. Randomized Packet Injection: This technique randomized data packets and injected into the communication stream between devices. Here we Inject random, malformed, or out-of-sequence packets into the PCIe link and mix valid and invalid IDE-encrypted packets to check the system’s ability to detect and reject unauthorized or invalid packets. Checking if encryption/decryption occurs correctly across packets. On verifying, we check if the system logs proper errors or alerts when encountering invalid packets. It ensures coverage of different data paths and robust protocol check. This technique helps assess the resilience of the IDE feature in PCIe in below terms: (i) Data corruption: Detecting if the system can maintain data integrity. (ii) Encryption failures: Testing the robustness of the encryption under random data injection. (iii) Packet ordering errors: Ensuring reordering does not affect data delivery. 2. Random Errors and Fault Injection: It involves simulating random bit flips, PCRC errors, or protocol violations to help validate the robustness of error detection and correction mechanisms of PCIe. These techniques help assess how well the PCIe IDE implementation: (i) Detects and responds to unexpected errors. (ii) Maintains secure communication under stress. (iii) Follows the PCIe error recovery and reporting mechanisms (AER – Advanced Error Reporting). (iv) Ensures encryption and decryption states stay synchronized across endpoints. 3. Traffic Pattern Randomization: Randomizing the sequence, size, and timing of data packets helps test how the device maintains data integrity under heavy, unpredictable traffic loads. Randomization for Data Encryption Verification Encryption adds complexity to verification, as encrypted data streams are not readable for traditional checks. Randomization becomes essential to test how encryption behaves under different scenarios. Randomization in data encryption verification ensures that vulnerabilities, such as key reuse or predictable patterns, are identified and mitigated. 1. Random Encryption Keys and Payloads: Randomly varying keys and payloads help validate the correctness of encryption without hardcoding assumptions. This ensures that encryption logic behaves correctly across all possible inputs. 2. Randomized Initialization Vectors (IVs): Many encryption protocols require a unique IV for each transaction. Randomized IVs ensure that encryption does not repeat patterns. To understand the IDE Key management flow, we can follow the below diagram that illustrates a detailed example key programming flow using the IDE_KM protocol. Figure 1: IDE_KM Example As Figure 1 shows, the functionality of the IDE_KM protocol involves Start of IDE_KM Session, Device Capability Discovery, Key Request from the Host, Key Programming to PCIe Device, and Key Acknowledgment. First, the Host starts the IDE_KM session by detecting the presence of the PCIe devices; if the device supports the IDE protocol, the system continues with the key programming process. Then a query occurs to discover the device’s encryption capabilities; it ensures whether the device supports dynamic key updates or static keys. Then the host sends a request to the Key Management Entity to obtain a key suitable for the devices. Once the key is obtained, the host programs the key into the IDE Controller on the PCIe endpoint. Both the host and the device now share the same key to encrypt and authenticate traffic. The device acknowledges that it has received and successfully installed the encryption key and the acknowledgment message is sent back to the host. Once both the host and the PCIe endpoint are configured with the key, a secure communication channel is established. From this point, all data transmitted over the PCIe link is encrypted to maintain confidentiality and integrity. IDE_KM plays a crucial role in distributing keys in a secure manner and maintaining encryption and integrity for PCIe transactions. This key programming flow ensures that a secure communication channel is established between the host and the PCIe device. Hence, the Randomized key approach ensures that the encryption does not repeat patterns. 3. Randomization PHE: Partial Header Encryption (PHE) is an additional mechanism added to Integrity and Data Encryption (IDE) in PCIe 6.0. PHE validation using a variety of traffic; incorporating randomization in APIs provided for validating PHE feature can add more robust Encryption to the data. Partial Header Encryption in Integrity and Data Encryption for PCIe has more detailed information on this. Figure 2: High-Level Flow for Partial Header Encryption 4. Randomization on IDE Address Association Register values: IDE Address Association Register 1/2/3 are supposed to be configured considering the memory address range of IDE partner ports. The fields of IDE address registers are split multiple values such as Memory Base Lower, Memory Limit Lower, Memory Base Upper, and Memory Limit Upper. IDE implementation can have multiple register blocks considering addresses with 32 or 64, different registers sizes, 0-255 selective streams, 0-15 address blocks, etc. This Randomization verification can help verify all the corner cases. Please refer to Figure 2. Figure 3: IDE Address Association Register 5. Random Faults During Encryption: Injecting random faults (e.g., dropped packets or timing mismatches) ensures the system can handle disruptions and prevent data leakage. Challenges of IDE Randomization and its Solution Randomization introduces a vast number of scenarios, making it computationally intensive to simulate every possibility. Constrained randomization limits random inputs to valid ranges while still covering edge cases. Again, using coverage-driven verification to ensure critical scenarios are tested without excessive redundancy. Verifying encrypted data with random inputs increases complexity. Encryption masks data, making it hard to verify outputs without compromising security. Here we can implement various IDE checks on the IDE callback to analyze encrypted traffic without decrypting it. Randomization can trigger unexpected failures, which are often difficult to reproduce. By using seed-based randomization, a specific seed generates a repeatable random sequence. This helps in reproducing and analyzing the behavior more precisely. Conclusion Randomization is a powerful technique in PCIe verification, ensuring robust validation of both data integrity and data encryption. It helps us to uncover subtle bugs and edge cases that a non-randomized testing might miss. In Cadence PCIe VIP, we support full-fledged IDE Verification with rigorous randomized verification that ensures data integrity. Robust and reliable encryption mechanisms ensure secure and efficient data communication. However, randomization also brings various challenges, and to overcome them we adopt a combination of constrained randomization, seed-based testing, and coverage-driven verification. As PCIe continues to evolve with higher speeds and focuses on high security demands, our Cadence PCIe VIP ensures it is in line with industry demand and verify high-performance systems that safeguard data in real-world environments with excellence. For more information, you can refer to Verification of Integrity and Data Encryption(IDE) for PCIe Devices and Industry's First Adopted VIP for PCIe 7.0 . More Information: For more info on how Cadence PCIe Verification IP and TripleCheck VIP enables users to confidently verify IDE, see our VIP for PCI Express , VIP for Compute Express Link for and TripleCheck for PCI Express For more information on PCIe in general, and on the various PCI standards, see the PCI-SIG website .




f

NClaunch : ncelab: *E,CUVHNF error

I'm trying to simulate a practice code . Verilog verification of my code do not give any error.But when I try to elaborate, this error is being showed:

ncelab: *E,CUVHNF (./FSM_test.v,17|20): Hierarchical name component lookup failed at 'l'

What does this mean? How can I debug this error ? Is there any archive or list of possible error list so that I don't have to ask in forum to understand the errors. 




f

A Guide to Build A Mini Guitar/Audio Amplifier Based on LM386

Hey, is it suitable to post here? I wanted a small yet robust amp for practicing while I travel. I wanted something that would fit in my pocket yet still be loud enough to hear.

Presented here is a amplifier based upon the LM386 Audio Amplifier.

There is a standard circuit in the data sheet that is an excellent place to start.

Materials needed:
1 - HM359 project box
1 - 668-1237 speaker
1 - BS6I battery conn
1 - CP1-3515 stereo jack
1 - SC1316 stereo jack
2 - 450-1742 knob
1 - 679-1856 switch
1- 3mm LED
1 - 10 ohm 1/4W resistor
1 - 10uF ceramic cap
1 - .05 uF ceramic cap
1 - 420 uF electrolytic cap
1 - 8 ohm resistor
2 - 51AADB24 10K pot
1 - HM1252 circuit board
1 - LM386N-4 amplifier

Wire and Solder
Step 1: Prep the enclosure

Careful planning is required the first time you free build a circuit. The circuit board has solder pads but not traces. You will have to use thin wire to make the connections for the circuit to work.

Begin by laying out the components on the circuit board that will need to pass through the enclosure. This enclosure has a removable top panel which will be used for the volume, gain and 1/4 inch stereo jack.

Space is limited to check for fit before drilling.

All drilling of the plastic should be done with a step drill bit. This will make the cleanest holes without breaking the plastic.

Lay out the pots a few spaces back but still in line with the desired position. mark the center of each pot shaft then drill with a step drill tot he tightest fitting hole size. Make a center mark between the pot holes then drill for the stereo jack

On the inside of the top cover position and mark where the speaker will go.

Make a template on grid paper the same size as the speaker.

Tape the template to the inside of the cover as shown then use a step bit to drill holes on the center of every square in the grid. This will form the speaker grille. clean up the holes.

Step 2: place the major components

Solder the pots to the circuit board as shown. then place the stereo jack(note in order to get the final fit I had to trim and modify the stereo jack housing a little)

Next, position and solder the switch on the circuit board and mark a space on the top cover that will need to be cut for the switch opening. Use a small file to cut the opening.

Use a sharp knife to bevel the edges of the switch hole to allow for easier operation.

Drill a hole in the side of the upper case for the headphone jack and fasten it in place. ( I had to recess the hole a bit for the retaining nut to grab)

Step 3: Build the circuit

The speaker is held in place by using 2 small brackets that come with the serial cable connector hood. ( I had a bunch around that would never be used)

Refer the the circuit shown from the datasheet and the datasheet for the LM386. The basic circuit only has the volume control while the datasheet shows how to add a gain control across pins 1 and 8 of the amplifier.

The speaker is wired in series with the headphone jack. The headphone jack has internal switches that shut the speaker off when the phones are plugged in.

I chose to use a chip socket for the amplifier which make prototyping easier since you do not have to worry about solder heating as much.

Carefully lay the circuit out on the board and begin wiring components together. I added a second pot and cap in series between pins 1 and 8 of the amp to be able to manually set the gain in addition to volume.

Check you connections with a multimeter before adding the amplifier.

I chose to add a LED indicator for power. This was done by using one side of switch contacts from the battery. The LED is in series with a 220 ohm resistor.

Assemble the case and insert the battery.

Step 4: Final notes

If the speaker is noisy while the headphones work normally, try reversing the speaker connections. If it does not correct the issue, connect a 8 ohm resistor across the speaker contacts.

You may have to place an insulating layer between the speaker and the place where the stereo jack comes through to prevent contact. This will be noted by a loud buzz.

You may have to add some foam in the battery compartment to stop the battery from banging around.

For reference, I've also read an article about amplifiers: http://www.apogeeweb.net/article/60.html

Thanks for reading!