Hi all, 

I have made a custom cell in Innovus that I will be instantiating into a bigger block, which I will also be using Innovus to do the Place & Route. 

I understand that I can generate a *.lef file and a *.lib file using Innovus. However, I need to also create a *.db file (these format of files are often used in DC Compiler synthesis tool). 

Is there a way to create the *.db file from Innovus? Or, is there a tool that I can use to create this *.db file? 

Thank you for your time. 

Hi everyone. 

I'm very a new cadence user. I'm not good at using it and quite lost in finding a way to get the results. With the topic, I would like to ask you for some suggestions to improve my cadence skills.

I have some digital decision logic. Some are combinational logic, some are sequential logic that I would like to import or generate random input combination to the inputs of my decision logic to get the maximum, minimum, and average delay power dissipation and area when feeding the different input combination.

My logic has 8-bit, 16-bit, and 32-bit input. The imported data tends to be decimal numbers.

I would like to ask you:

- which tool(s) are the most appropriate to import and feed the different combination to my decision logic?

- which tool is the most appropriate to synthesis with different number of input? - I have used Genus Synthesis Solution so far. However with my skill right now I can only let Genus synthesize my Verilog code one setup at a time. I'm not sure if I there is anyway I can feed a lot of input at a time and get those results (min, max, average of delay, power dissipation and area)

- which language or scripts I should pick up to use and achieve these results?

-where can I find information to solve my problem? which information shall I look for?

Thank you so much for your time!!

Best Regards

I have a 2-dimensional input in my design - input [2:0] data_in [15:0]. After synthesis with genus, I got a netlist where the inputs are like data[15], data[14],...,data[0]. And furthermore it has definitions like input [2:0] data[15], .... So how can I define the pin locations of each of the bits for this input? Can I define data[15]'s inner bits like data[15][0]? Is it possible to define this with def files?

Hi! I've made some 1-point waveform "markers" that I want to overlay in my plots to aid visualization (with the added advantage, w.r.t. normal Viva markers, that they update location automatically upon refreshing simulation data).

For example, the plot below shows an spectrum along with two of these markers, which I create with the function "singlePointWave", and the Assembler output definitions also as shown below.

The problem is: as currently created and defined, Assembler is unable to plot these elements. I can send their expressions to the calculator and plotting works from there, BUT ONLY after first enabling the "Allow Any Units" in the target Viva subwindow.

Thus, I suspect Assembler is failing to plot my markers because they "lack" other information like axes units and so on. How could I add whatever is missing, so that these markers can plot automatically from Assembler?

Thanks in advance for any help!

Jorge.

P.S. I also don't know why, but nothing works without those "ymax()" in the output definitions--I suspect they are somehow converting the arguments to the right data type expected by singlePointWave(). Ideas how to fix that are also welcome! ^^

procedure( singlePointWave(xVal yVal)
    let( (xVect yVect wave)
        xVect = drCreateVec('double list(xVal));
        yVect = drCreateVec('double list(yVal));
        wave = drCreateWaveform(xVect yVect);
    );
);

I want to create sub tree of sub trees how can i do that?

I want to create another tree for the Sub parameter also.

What is the variable to define via selection/type for vias

I want to be able to load via cut type in the via option when I use the leHiCreateVia() function

I want to select/load to the Via Option menu on which via I want to use

Cadence version IC23.1.64b.ISR7.27

Paul

I am attempting to use dbGetNeighbor() function inside the dynamic display HUD so that the distance to the next metal on that layer could be viewed. Think of another line in this dynamic table here... 

My SKILL code is essentially the following:

procedure(getNearestNeighborOnMetal(cv)
let((direction tmpBoundingBox)
direction = internal_function()
tmpBoundingBox = dbCreateRect(geGetEditCellView() "tmp" list(hiGetCommandPoint() hiGetCommandPoint()))
car(dbGetNeighbor(geGetEditCellView() tmpBoundingBox direction))
)
)

this returns the distance to the closest metal based on some tests.

Next, I try to register this function to work in the Dynamic Display / Info Balloon world by executing odcRegisterCustomFunc() for each and every object type (I know, absurd, but trying to debug)

In the dynamic display menu, I toggle the "Custom SKILL Function" check in layoutXL, then hit apply, then OK.

After this I find I am unable to view the changes reflected in any info balloons or in the drawing HUD (above) for this wire. I have tried replacing my function with the sample "customFunc" from the odcRegisterCustomFunc() documentation and was still unable to produce any new output.

Any help diagnosing the use of this feature would be very much appreciated

Hi,

My query is regarding importing of layout.

After importing, we see that the imported transistor instances and vias are all referring to the library in which they are imported, instead of referring to the technology library.

Please let me know how we can refer them to the technology library.

Will surely provide more details if my query is unclear.

Thanks,

Mallikarjun.

Hello,

I would like to create a button for my form that prompts the user to click on a cellview and draw a rectangle bounding box, exactly like the one used in the Area and Density Calculator. Can someone please help me with this?

Thanks!

Beto

Hi All,

I'm using a code (abConvertPolygonToPath.ils) that I found in other posts to convert a rect object to a path object inside a pcell code, but when I try to run a DRC, the layout export fails due to a warning message, here is the log message

*WARNING* (DB-270001): Pcell evaluation for 18A_asaavedr/lay_mesh_BM0_BM4_3p6_3p6/layout has the following error(s):

*WARNING* (DB-270002): ("eval" 0 t nil ("*Error* eval: undefined function" abConvertPolygonToPath))

ERROR (XOASIS-231): Pcell evaluation failed for '18A_asaavedr/lay_mesh_BM0_BM4_3p6_3p6/layout' because the Pcell SKILL code contains either a syntax error or an unsupported XOasis function. Check the standard output or the Virtuoso log file for more information. Cadence recommends correcting the Pcell SKILL code to resolve the issue. However, to ignore these errors and continue the translation, you may use the 'ignorePcellEvalFail' option.

INFO (XOASIS-282): Translation Failed. '1' error(s) and '3' warning(s) found.

And when compile the code I get the following message:

*WARNING* defgeneric function already defined - abConvertPolygonToPath

I will aprreciate any help in how to waive this error, or fix it.

Thank you

Disappearing toolbar or docked menu

Is there a way for the toolbar or floating menu from disappearing when a cells tab is added to a window?

I have created a skill toolbar and it disappeared when I add another cell or tab to a window.

The only toolbars that stay are the ones I have defined in the Layout.toolbar file.

Do I have to add a trigger to keep the toolbars visible or not disappearing from the window?

Cadence version IC23.1-64b.ISR7.27

Paul

Hi,

I want to define a procedure that with @key, and I also want to restrict the variable's datatype, I tried with folloing but I received error in CIW

procedure(tt(handler @key str1 str2 "ssS")
  printf("handler: %L " handler)
)

tt('test)

The error is like: *Error* tt: argument for keyword ?str1 should be a symbol (type template = "ssS") at line 11 of file

Thanks,

James

Hello,

I was looking to destructively and efficiently modify a list that was passed in as an argument to a procedure, by prepending an item to the list.

I noticed that cons lets you do this efficiently, but the operation is non-destructive. Hence this wouldn't work if you are trying to modify a function's list parameter in place.

Here is an example of trying to add "0" to the front of a list:

By David Vye, Senior Product Marketing Manager, AWR, Cadence When designing multi-octave high-power amplifiers, it is a challenge to achieve both broadband gain and power matching using a combination of lumped and distributed techniques. One approach...(read more)

Hello All:

I am looking for help on the following, as I am new to Cadence tools [I have to use Cadence Innovus for Physical Design after Logic Synthesis using Synopsys Design Compiler, using Nangate 45 nm Open Cell Library]: while using Cadence Innovus, I would need to select a few specific nets to be routed through a specific metal layer. How can I do this on Innovus [are there any command(s)]? Also, would writing and sourcing a .tcl script [containing the command(s)] on the Innovus terminal after the Placement Stage of Physical Design be fine for this?

Secondly, is there a way in Innovus to manipulate layout components, such as changing some pin placements, wire directions (say for example, wire direction changed to facing east from west, etc.) or moving specific closely placed cells around (without violating timing constraints of course) using any command(s)/.tcl script? If so, would pin placement changes and constraining some closely placed cells to be moved apart be done after Floorplanning/Powerplanning (that is, prior to Placement) and the wire direction changes be done after Routing? 

While making the necessary changes, could I use the usual Innovus commands to perform Physical Design of the remaining nets/wires/pins/cells, etc., or would anything need modification for the remaining components as well?

I would finally need to dump the entire design containing all of this in a .def file.

I tried looking up but could only find matter on Virtuoso and SKILL scripting, but I'd be using Innovus GUI/terminal with Nangate 45 nm Open Cell Library. I know this is a lot, but I would greatly appreciate your help. Thanks in advance.

Riya

I am scripting gds streamin using 'strmin', which works fine so far.

But, as it apparently doesn't have an option to specify where the cds.lib file is, I have to run it from the directory where the cds.lib file is, or I guess I could create a dummy one to source that one.

Is there a way to tell strmin where the cds.lib file is?

We are looking for suitable tools that could be used for RTL design, IP-XACT based  integration (third party IP) and RTL design verification ( SV / UVM based methodology).

Request to share details on the different Cadence tools that is most suitable for these activities.

I am not able to open 64bit version of simvision using the following :

simvision -64 -wav "path to wav"

This throws the error "  /lib64/libc.so.6: version `GLIBC_2.14' not found"

I am only able to open it without the -64 option.

As a result I am not able to use the source browser feature since the simulation was run in 64 bit mode.

Need suggestion on how to resolve this. Thanks.

Hi everyone, 

Is there any method to generate "Sheet" column for a pin report like table below? The column "Name.Pin" & "Signal" can be generated easily, but I have no idea to generate the column of "Sheet Name".

The software using here are Allegro Design Entry HDL, OrCAD Capture and Allegro PCB Editor. Can these 3 software generate "Sheet Name" data?

Thank you. 

Good morning,
I dug up an old project from 2005 and I should open the schematic to check some things.
This is the schematic of a XILINX XC95108-pq160 CPLD which the XILINX ISE 6.1 software then translated and compiled, to generate a JEDEC file to burn CPLD.

My problem is that I can't open schematics with the versions of Orcad Schematic Entry that I have.
Can anyone help me understand which version of Orcad Schematic Entry I need to install to see these files?

I shared the files on:
drive.google.com/.../view

Thank you very much

Hi, have two designs and would like to copy paste one area of circuit from the old design to the new design, best way/approach and guidance please..

hi

How can I tell the LEC tool to ignore a combination of Primary input bus in both Golden and revised.

For example in both Golden and revised there is 

input [3:0] data_in

I want LEC not to check the case that data_in[3:0] == 4'b1000

I want to use a transmission gate in my design, but it is not available as a standard cell for Genus RTL synthesis. How can I perform an analysis of area, power, and critical path delay that includes the transmission gate alongside standard cells?

Could you provide guidance or a methodology for integrating custom cells, like the transmission gate, into the synthesis flow for accurate analysis?

I am trying to understand the Linting process. I know that mainly JasperGold is the tool for this purpose. Though I think JasperGold is more suited for later stages of the design. As a RTL Design Engineer, I want to make sure that if another tool has the capability of doing Linting earlier in the flow. for example, does Xcelium, Genus or Confomal support linting. I have seen some contradicting information online regarding this topic, though I can't find anything related to Linting on any of these tools.

Thanks

The automotive industry revolutionized the definition of a vehicle in terms of safety, comfort, enhanced autonomy, and internet connectivity. With this trend, the automotive industry rapidly adopted automotive Ethernet such as 10Base-T1, 100Base-T1, and in some cases, 1000Base-T1. 

Faster Speed (than CAN-FD), Scalability, embedded security protocols (like MacSec), cost and energy efficiency, and simple yet redundant network made Ethernet an obvious choice over CAN(FD) and FlexRay.  

Ethernet 10Base-T1 

10BASE-T1S is defined under IEEE with 802.3cg. The S in 10BASE-T1S stands for a short distance. 10BASE-T1S uses a multidrop topology, where each node connects to a single cable. Multidrop topology eliminates the need for switches and, as a result, fewer cables/less cost. The primary goal of 10BASE-T1S is a deterministic transmission on a collision-free multidrop network. 10BASE-T1S cables use a pair of twisted wires. As per IEEE, at least eight nodes can connect to each, but more connections are feasible.    

The Physical Layer Collision Avoidance [PLCA] protocol ensures that it uses the entire 10 Mbps bandwidth. In 10BaseTs, Reconciliation Sublayer provides optional Physical Layer Collision Avoidance (PLCA) capabilities among participating stations. Using PLCA-enabled Physical Layers in CSMA/CD half-duplex shared-medium networks can provide enhanced bandwidth and improved access latency under heavily loaded traffic conditions. The working principle of PLCA is that transmit opportunities on a mixing segment are granted in sequence based on a node ID unique to the local collision domain (set by the management entity). 10BASE-T1S also supports an arbitration scheme that guarantees consistent node access to the media within a predefined time.  

The 10BASE-T1S PHY is intended to cover the low-speed/low-cost applications in the industrial and automotive environment. A large number of pins (16) required by the MII interface is one of the significant cost factors that must be addressed to fulfill this objective. The 10BASE-T1S "Transceiver" solution is suited for embedded systems where the digital portion of the PHY is fully integrated, e.g., into an MCU or an Ethernet switch core, leaving only the analog portion (the transceiver) into a separate IC. 

Ethernet 100Base-T1/1000Base-T1 

100Base-T1 and 1000Base-T1 can be used for audio/video information. With Higher bandwidth capacity, 100Base-T1/ 1000Base-T1 paired with AVB (Audio video bridging) can be used for car infotainment systems. 100Base-T1/1000Base-T1 paired with time-sensitive networking [TSN] protocol can be used to fulfill the automotive industry's mission-critical, time-sensitive, and deterministic latency needs. 

 PTP Over MacSec  

With today's automotive network, all the Electronic Control Units connected require timing accuracy and network synchronization, Precision Time Protocol (PTP), defined in IEEE 1588, provides synchronized clocks throughout a network.  While maintaining the timing accuracy for mission-critical applications, protecting the vehicle network from vulnerable threats is mandatory, and PTP over MacSec provides the consolidated solution.  

With the availability of the Cadence Verification IP for 10/100/1000BaseT1 and TSN, adopters can start working with these specifications immediately, ensuring compliance with the standard and achieving the fastest path to IP and SoC verification closure. The 10/100/1000GBaseT1 and TSN provide a full-stack solution, including support to the PHY, MAC, and TSN layers with a comprehensive coverage model and protocol checkers. Ethernet BaseT1 and TSN VIP covers all features required for complete coverage verification closure. More details are available in the Ethernet Verification IP portfolio. 

Krunal 

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)

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 

In a network containing multiple nodes, the need for synchronization between the various nodes is not just instrumental but also a complicated and highly complex process. This process becomes even more tricky if we synchronize the clocks between the Manager and the Peripheral. As we know, in a real-time network, some of the nodes would behave like Managers while some would be a Peripheral. If we must make the communication process smooth, then the local clocks of these nodes must be synchronized. 

The problem with this synchronization is that we have the clock running in the Manager as well. If we send the value of the Manager clock to the Peripheral, the synchronization doesn’t happen as we have a propagation delay of the messages, along with the propagation delay of the electronic circuits of Manager and the Peripheral.  

The cherry on the cake is that these electronic circuit propagation delays are not random and remain constant, so we can add a time offset to it to match the clock. To tackle this challenge, IEEE has come up with a protocol named “Precision Timing Protocol.” 

Operation of PTP: 

To synchronize the clocks, a Sync message is sent by the Manager to the Peripheral, which then timestamps the receiving time of the same. Following this, a ‘Follow up’ message is issued by the Manager stating the timestamp at which the Sync message was sent. 

The Peripheral then finds the difference between the two values and adds this to its current time. After this, the time difference between the Manager and the Peripheral narrows down to only the propagation delay of the messages.  

To overcome this, the Peripheral issues a ‘Delay Request’ to the Manager, and the Manager, in turn, issues a ‘Delay Response.’ Both these messages have the timestamp of when they were issued. The time at which they are received is then noted. Since two messages are sent, one from the Peripheral and the other from the Manager, there are two propagation delays. Then half of this value is our propagation delay. 

The Peripheral then adds this propagation delay to its clock, and hence the clock gets synchronized. 

Advantages of PTP: 

1. It provides accurate time stamping. 
2. It is a well-known clock synchronization protocol. 
3. It provides intensified security inside the premises. 
4. It provides the possibility of setting coordinated actions and synchronized communication. 

There are various versions of PTP that have been developed over time, namely PTPv1, PTPv2, PTPv2_1, and the latest PTP-AS. 

Cadence Verification IP for Ethernet is available to support the newer version of PTP, allowing simulation of the 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. 

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)

Power network design and analysis of 3D-ICs is a major challenge due to the complex nature and large size of the power network. In addition, designers must deal with the complexity of routing power through the interposer, multiple dies, through-silicon vias (TSVs), and through-dielectric vias (TDVs).
Cadence’s Integrity 3D-IC Platform and Voltus IC Power Integrity Solution provide a fully integrated solution for early planning and analysis of 3D-IC power networks, 3D-IC chip-centric power integrity signoff, and hierarchical methods that significantly improve capacity and performance of power integrity (PI) signoff while maintaining a very high level of accuracy at signoff. This blog summarizes the typical design challenges faced by today’s 3D-IC designers, as discussed in our recent webinar, “Addressing 3D-IC Power Integrity Design Challenges.” Please click here to view the full webinar.

Major Trends in Advanced Chip Design

From chips to chiplets, stacked die, 3D-ICs, and more, three major trends are impacting advanced semiconductor packaging design. The first is heterogenous integration, which we define as a disaggregated approach to designing systems on chip (SoCs) from multiple chiplets. This approach is similar to system-in-package (SiP) design, except that instead of integrating multiple bare die – including 3D stacking – on a single substrate, multiple IPs are integrated in the form of chiplets on a single substrate.

The second major trend is around new silicon manufacturing techniques that leverage silicon vias (TSVs) and high-density fanout RDL. These advancements mean that silicon is becoming a more attractive material for packaging, especially when high bandwidth and form factor become key attributes in the end design. This brings new design and verification challenges to most packaging engineers who typically work with organic and ceramic substrate materials.

Finally, on the ecosystem side, all the large semiconductor foundries now offer their own versions of advanced packaging. This brings new ways of supporting design teams with technologies like reference flows and PDKs, concepts that have typically been lacking in the packaging community. Cadence has worked with many of the leading foundries and outsourced semiconductor assembly and test facilities (OSATs) to develop multi-chip(let) packaging reference flows and package assembly design kits. The downside is that, with the time restrictions designers are under today, there isn’t enough time to simulate the details of these flows and PDKs further.

For those who must make the best electro/thermal/physical decisions to achieve the best power/performance/area/cost (PPAC), factors can include accurate die size estimations, thermal feasibility, die-to-die interconnect planning, interposer planning (silicon/organic), front-to-front and front-to-back (F2F/F2B) planning, layer stack and electromigration/ IR drop (EMIR)/TSV planning, IO bandwidth feasibility, and system-level architecture selection.

3D-IC Power Network Design and Analysis

The key to success in 3D-IC design is early power integrity planning and analysis. Cadence’s Integrity 3D-IC platform is a high-capacity 3D-IC platform that enables 3D design planning, implementation, and system analysis in a single, unified cockpit. Cadence’s Voltus IC Power Integrity Solution is a comprehensive full chip electromigration, IR drop, and power analysis solution. With its fully distributed architecture and hierarchical analysis capabilities, Voltus provides very fast analysis and has the capacity to handle the largest designs in the industry. Typically, 3D-IC PDN design and analysis is performed in four phases, as shown in Figure 1.

Phase 1 - Perform early power delivery network (PDN) exploration with each fabric’s PDN cascaded in system PI with early circuit models.

Phase 2 – Plan 3D-IC PDNs in Cadence’s Integrity 3D-IC platform, including micro bumps, TSVs, and through dielectric vias (TDVs), power grid synthesis for dies, and early rail analysis and optimization.

Phase 3 – Perform full chip-centric signoff in Voltus with detailed die, interposer, and package models, including chip die models, while keeping some dies flat.

Phase 4 – Perform full system-level signoff with Cadence’s Sigrity SystemPI using detailed extracted package models from Sigrity XtractIM, board models from Sigrity PowerSI or Clarity 3D Solver, interposer models from XtractIM or Voltus, and chip power models from Voltus.

Figure 1. 3D-IC PDN design and analysis phases

3D-IC Chip-Centric Signoff

The integration of Integrity 3D-IC and Voltus enables chip-centric early analysis and signoff. Figure 2 and Figure 3 highlight the chip centric early PI optimization and signoff flows. In early analysis, the on-chip power networks are synthesized, and the micro bumps and TSVs can be placed and optimized. In the signoff stage, all the detailed design data is used for power analysis, and detailed models are extracted and used for package, interposer, and on-die power networks.

Figure 2. Early chip-centric PI analysis and optimization flow

Figure 3. Chip-centric 3D-IC PI signoff

Hierarchical 3D-IC PI Analysis

To improve the capacity and performance of 3D-IC PI analysis, Voltus enables hierarchical analysis using chiplet models. Chiplet models can be reduced chip models in spice format or more accurate xPGV models which are highly accurate proprietary models generated by Voltus. With xPGV models, the hierarchical PI analysis has almost the same accuracy as flat analysis but offers 10X or higher benefit in runtime and memory requirements.

Conclusion

This blog has highlighted the major design trends enabled by advanced 3D packaging and the design challenges arising from these advancements. The design of power delivery networks is one of these major challenges. We have discussed Cadence solutions to overcome this PI challenge. To learn more, view our recent webinar, "Addressing 3D-IC Power Integrity Design Challenges" and visit the Voltus web page.

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)

Live Doc is an advanced automated PCB documentation generation tool integrated with OrCAD X Presto designed to streamline the creation of PCB documentation. By automating the generation of PCB fabrication and assembly drawings, Live Doc significantly...(read more)

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. 

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.

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?  

Starting from SPB23.1, a new option, Allow DRCs to surrounding metal, has been added in the Etch-Back form to allow DRCs to the surrounding objects. form to allow DRCs to the surrounding objects.

The Allow DRCs to surrounding metal option lets you see and adjust objects instead of the current behavior, which sacrifices the width of the mask for the trace.

• When this option is turned off, it maintains the EB mask to another object clearance.
• When this option is enabled, it keeps the EB mask to the EM trace edge clearance and shows a DRC if the EB mask to another object spacing is out of rule.

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.

Have you ever thought of a handy utility to specify all necessary transmission line parameters to decide upon the stackup?   

Starting SPB 23.1, a handy feature Transmission Line Calculator, is built into Allegro X Advanced Package Designer (Allegro X APD). This feature will require either an SiP Layout license or can be accessed through SiP Layout Bundle. 

From the Analyze dropdown menu in the 23.1 Allegro X APD toolbar, you can choose Transmission Line Calculator. 

You can use this calculator to help decide constraints and stackup for laminate-based PCB or Packages. You can calculate the correct stackup material and width/spacing to meet any requirements that may be later entered in a constraint. This is truly a calculated number and not a true field solver. 

The different types of calculations that the Transmission Line Calculator can provide are Microstrip, Embedded microstrip, Stripline, CPW (Coplanar), FGCPW (frequency-dependent Coplanar), Asymmetric stripline, Coupled microstrip (Differential Pair), Coupled stripline (Differential Pair), and Dual striplines. 

This feature is important for customers relying on fabricators/spreadsheets to provide this information or need to test a quick spacing/width as per the impedance value. 

Let us know your comments on this new feature in 23.1 Allegro X APD. 

Starting SPB 23.1, Allegro X APD lets you import/export the symbol and component properties by using Die Text-In/Out wizards. 

Exporting the symbol 

You can export the symbol by using File > Export > Die Text-Out Wizard. 

In the Die Text-Out Wizard window, you can see the newly added options, that is, Component Properties and Symbol Properties. 

This entire information including the properties will be saved in a text file. 

Importing the symbol 

You can import the same text file in Allegro X APD by using Die Text-In Wizard. 

Choose the text file you want to import. 

Symbol properties added in the text file will be visible in the Die Text-In Wizard window. 

Hi，

I want to delete via use skill，but i dont write this skill. can you help me.

This skill has Interactive interface，the interface can imput  Select Net and select padstack；

I can  use temp group to select the via；

example，i want to delete via，the padstack is L1:L3，the net is vss. i can imput padstack  L1:L3 and select net: VSS；

Note: The green is VSS，the padstack L1:L3 and L3:L5 ；

thanks

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.

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. 

In a package design, designers often need to perform degassing. This is typically done at the end of the design process before sending the design to the manufacturer.

Degassing is a process where you perforate power planes, voltage planes, and filled shapes in your design. Degassing holes let the gas escape from beneath the metal during manufacturing of the substrate. The perforations or holes for degassing are generally small, having a specified size and shape, and are spaced regularly across the surface of the plane. If the degassing process is not done, it may result in the formation of gas bubbles under the metal, which may cause the surface of the metal to become uneven. After you degas the design, it is recommended to perform electrical verification.

Allegro X APD has degassing features that allow users to automate the process and place holes in the entire shape.

In today’s topic, we will talk about how to avoid adding  degassing holes on a particular shape.

Sometimes, a designer may need to avoid adding degassing holes to a particular shape on a layer. All other shapes on the layer can have degassing holes but not this shape. Using the Layer Based Degassing Parameters option, the designer can set the degassing parameters for all shapes on the layer. Now, the designer would like to defer adding degassing holes for this particular shape.

You may wonder if there is an easy way to achieve this. We will now see how this can be done with the tool.

Once the degassing parameters are set, performing Display > Element on any of the shapes on that layer will show the degassing parameters set.

You can apply the Degas_Not_Allowed property to a shape to specify that degassing should not be performed on this shape, even if the degassing requirements are met. Select the shape and add the property as shown below.

Switch to Shape Edit application mode (Setup > Application mode > Shape Edit) and window-select all shapes on the layer. Then, right-click and select Deferred Degassing > All Off.

Now, all shapes on the layer will have degassing holes except for the shape which has the Degas_Not_Allowed property attached to it.

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.

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.

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? 

The DBDoctor application checks the database for errors and other problems, and presents a report about them. DBDoctor supports .brd, .mcm, .mdd, .psm, .dra, .pad, .sav, and .scf databases.

DBDoctor can:

• Analyze and fix database problems.
• Eliminate duplicate vias.
• Perform batch design rule checking (DRC).
• Upgrade databases more than one revision old.

To verify the integrity of a drawing database at any time during the design cycle, run DBDoctor at regular intervals but make sure you always run it after completing a design.

You can run DBDoctor to verify work in progress, or from a terminal window outside the layout editor, perhaps to check multiple input designs in batch mode by using wildcards and various switches. You do not have to run the layout editor to use DBDoctor.

To run this from Allegro X APD and Allegro PCB Editor, go to Tools > Database Check.

You can also go to the Start menu and select Cadence PCB Utilities 2023 > PCB DB Doctor 2023.

You can also use the following command to run DBDoctor in batch mode in the system command prompt:

dbdoctor [-check_only] [-drc] [-drc_only] [-shapes][-no_backup] [-outfile <newboardname.brd>]>

Comment below if you want to know more about this command and its integration with SKILL programming!!

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):

• Using SimAI with vManager (For Regression Compression and Coverage Regain) (RAK) 
• Using SimAI with a Generic Runner (For Regression Compression and Coverage Regain) (RAK)

2. 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:

• Using SimAI for Coverage Maximization - vManager flow (RAK) 
• Using SimAI for Coverage Maximization - Generic Runner Flow (RAK)

3. 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:

• Using SimAI for Bug Hunting with vManager (RAK) 
• Using SimAI for Bug Hunting – Generic runner flow (RAK) 

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!

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.