A wearable device has a carrier having an aperture. A device has a USB connection and a protrusion wherein the protrusion is received in the aperture to connect the device to a wristband. The device is a USB type device having athletic functionality. The device may further be configured to receive calibration data such that a measured distance may be converted to a known distance based on athletic activity performed by a user.

Methods, devices and system are provided. One method includes capturing activity data associated with activity of a user via a device. The activity data is captured over time, and the activity data is quantifiable by a plurality of metrics. The method includes storing the activity data in storage of the device and, from time to time, connecting the device with a computing device over a wireless communication link. The method defines using a first transfer rate for transferring activity data captured and stored over a period of time. The first transfer rate is used following startup of an activity tracking application on the computing device The method also defines using a second transfer rate for transferring activity data from the device to the computing device for display of the activity data in substantial-real time on the computing device.

A reset circuit for Gate Driver on Array, an array substrate and a display is used for increasing reliability and long-term stability of a GOA circuit and thus improving performance of the GOA circuit. The GOA reset circuit includes a first electronic switch circuit (301) connected to an input terminal of a GOA unit of the Gate Driver on Array (INPUT); and a second electronic switch circuit connected to an output terminal of the GOA unit (OUTPUT), wherein the first electronic switch circuit (301) is connected to a low level signal terminal and is switched on to connect the low level signal terminal to a reset terminal of the GOA unit (RESET) when the input terminal of the GOA unit (INPUT) is at a high level; and the second electronic switch circuit (302) is connected to a high level signal terminal and is switched on to connect the high level signal terminal to the reset terminal of the GOA unit (RESET) when the output terminal of the GOA unit (OUTPUT) is at a high level.

A method and system for synchronizing the output signal phase of a plurality of frequency divider circuits in a local-oscillator (LO) or clock signal path is disclosed. The LO path includes a plurality of frequency divider circuits and a LO buffer for receiving a LO signal coupled to the plurality of frequency divider circuits. The method and system comprise adding offset voltage and setting predetermined state to each of the frequency divider circuits; and enabling the frequency divider circuits. The method and system includes enabling the LO buffer to provide the LO signal to the frequency divider circuits after they have been enabled. When the LO signal drives each of the frequency divider circuits, each of the frequency divider circuits starts an operation. Finally the method and system comprise removing the offset voltage from each of the frequency divider circuits to allow them to effectively drive other circuits.

An open loop clock divider circuit includes (a) a first divider configured to receive an incoming clock signal and output a first divided clock signal, (b) a flying-adder synthesizer configured to fractionally divide the first divided clock signal and output a fractionally divided clock signal, and (c) a second divider configured to receive the fractionally divided clock signal and output a second divided clock signal. The open loop clock divider circuit advantageously provides a fractional divider in which there is no feedback loop between the source frequency (fs) and the destination frequency (fd). Methods of generating a divided clock signal involving the open loop clock divider circuit are also disclosed.

One of the most important RF building blocks today is the frequency synthesizer, or more particularly the programmable frequency divider (divider). Such dividers preferably would support unlimited range with continuous division without incorrect divisions or loss of PLL lock. The inventors present multi-modulus dividers (MMDs) providing extended division range against the prior art and without incorrect divisions as the division ratio is switched back and forth across the boundary between two different ranges. Accordingly, the inventors present MMD frequency dividers without the drawbacks within the prior art.

A display apparatus and a method for generating gate signal thereof are provided. The display apparatus includes a timing controller and a display panel. The timing controller is used for providing a plurality of timing signals. The display panel includes a pixel array and a gate drive circuit. The pixel array has a plurality of pixels. The gate drive circuit is electrically connected to the timing controller and the pixel array and including a plurality of shift register circuits. The shift register circuit includes a first shift register and a second shift register. The first shift register is configured for generating a corresponding primary gate signal. The second shift register is configured for generating a corresponding secondary gate signal. The timing controller adjusts overlapping relations of the timing signals according to a frame rate of the display apparatus.

A system for optimizing storage in an enclosed transport trailer (6), having transverse bearing beams (2) for supporting a load such as loaded pallets (12, 13) at a mid height of the trailer such that two storage levels are available. The beams have a wheel (10) at each end that runs in a horizontal track (11) attached to each side wall of the trailer, the track enclosing the wheels to prevent them from disengaging from the track. Adjacent beams can be attached together at variable spacings using a spacer bar (15) to suit a particular pallet or load size. The track has a junction adjacent the open end (20) of the trailer that leads up to another track (18) immediately below the roof line where the beams can be moved to an out of the way storage position (19) when not required.

A vehicle restraint system includes a strap assembly configured to be positioned on a portion of a tire of a vehicle to secure the vehicle to a deck of a transport. The strap assembly is also configured to be coupled to the deck of the transport on a first side of the tire of the vehicle. The system also includes a mandrel assembly operable to be coupled to the strap assembly on a second side of the tire of the vehicle, opposite the first side. The system further includes a winch assembly configured to be coupled to the deck of the transport and the mandrel assembly on the second side of the tire of the vehicle, the winch assembly configured to rotate the mandrel assembly to produce a tightening force to tighten the strap assembly around the portion of the tire. The system still further includes a release mechanism disposed between the winch assembly and the mandrel assembly and configured to create a coupling between the winch assembly and the mandrel assembly in a manner that transmits the tightening force from the winch assembly to the mandrel assembly. The release mechanism is configured to release the coupling between the winch assembly and the mandrel assembly when a force greater than or equal to a predetermined force is produced against the release mechanism.

There is provided a transport vehicle for transporting wind power installation rotor blades and/or pylon segments. The transport vehicle has a transport support structure having a main frame, a receiving frame fixedly connected to the main frame at a first angle, and a rotary displacement unit which is fixed with one end to the receiving frame and which at its second end has a blade adaptor for receiving a rotor blade or a pylon segment. The main frame spans a main plane. The rotary displacement unit has at least one first rotary mounting, wherein there is provided a second angle between the second rotary plane of the second rotary mounting.

A transportation and storage system for a wind turbine rotor blade comprises a tip end frame assembly comprising a tip end receptacle and a tip end frame. The tip end receptacle comprises an upwardly open tip end-receiving space for receiving a portion of the tip end of the blade and having a supporting surface for supporting the blade, a lower surface allowing the tip end receptacle to rest upright on a substantially horizontal surface, such as the ground, and releasable retaining means for releasably retaining the tip end of the blade in the receiving space of the tip end receptacle. The tip end frame comprises an upwardly open receptacle-receiving space for receiving the receptacle and provided with positioning means for positioning the receptacle in the tip end frame. A base part defines a bottom surface allowing the tip end frame to rest upright on the ground.

A transport system for transporting large items wherein the large items comprise at least three through going holes and said system comprises a frame to support the items. Said frame has a substantially rectangular shape and comprises two parallel longitudinal beams connected by two parallel transverse beams and further comprises at least two transverse support bars to support the items, which transverse support bars are located between the two parallel transverse beams. The transport system further comprises a first and a second rod to be mounted in two through going holes in the items where each end of the first and second rod can be connected to the longitudinal beams to secure the items to the frame in such a way that no part of the large items extends over the rectangle defined by the two parallel longitudinal beams and the two parallel transverse beams.

An apparatus for securing a cargo item within a cargo area that is defined by a pickup truck bed and a bed liner that is disposed within the pickup truck bed, the bed liner defining a plurality of elongate grooves. The apparatus includes a rod that extends along an axis in an axial direction of the rod. An engaging structure is receivable within at least one groove from the plurality of elongate grooves of the bed liner for engagement with the bed liner. An adjustable connecting structure connects the engaging structure to the rod and allows adjustment of an axial position of the engaging structure along the rod in the axial direction of the rod. A body is connected to the rod for engaging the cargo item.

A load carrier includes a load changing frame that has first and second end portions. The load changing frame has two longitudinal frame beams, two transverse frame beams arranged at the end portions of the load changing frame, and a first, upwardly tapering lifting stand. The second end portion of the load changing frame includes a second lifting stand, which is shaped and arranged in accordance with the first lifting stand. The transverse frame beams are elongated to extend outward from the longitudinal frame beams for mounting of supports facing the support surface. A plurality of such load carriers are adapted to be stacked on top of each other, wherein each overlying load carrier with its lifting stands is adapted to straddle the lifting stands of the underlying load carrier vertically from above, wherein the length of the stack corresponds to the length of the load carrier.

Some embodiments include a novel laced strapping system that provides a plurality of attachment points by which a tie-down lace can adjust the fit of a cargo mesh webbing to secure loads of items in an open bed of a vehicle. In some embodiments, the vehicle is a pick-up truck with a cargo bed. In some embodiments, the mesh webbing comprises a first truck bed mesh, a second truck bed mesh, and the plurality of attachment points. In some embodiments, tie-down lace interconnects the attachment points to secure together the first mesh and the second mesh.

Some embodiments of the invention relate to function elements for fixing in seat rails of aircraft. The function element according to the invention may include: a fixing rail with a web running in the x direction and a multiplicity of extensions which protrude beyond the web in a y direction to form a T profile, wherein the fixing rail is formed corresponding to the seat rail such that the fixing rail can be inserted in the seat rail and moved along the x direction into a holding position in which the extensions sit between the holes below the slots, at least one fixing peg which is arranged mobile on the fixing rail and can be brought into a blocking position in which the fixing peg engages in a hole of the seat rail so that the function element is fixed in the x direction.

An improved captive beam decking system is disclosed for use in a cargo trailer. The system includes a beam assembly and a foot assembly that is selectively engagable to a vertical sliding track system. The sliding track system is attached to the sidewall of a trailer vertically. The beam can be easily moved at different heights that are selected based upon the configuration of the cargo trailer.

Stake pocket formations are secured to a cargo bed frame of a land vehicle such as trailers and flatbed trucks for removably supporting sidewall supporting members. The formations include sidewalls secured to and projecting from the frame and an end wall extending between the sidewalls. An opening extends through the end wall and is adapted to receive the terminal end of a J-hook therethrough. The J-hook is secured to the formation by inserting the terminal end thereof into the pocket placing an upper edge of the end wall into the J-hook gap and rolling/rotating the J-hook thereby inserting the terminal end into the opening. The J-hook cannot be removed from the pocket unless it is rolled/rotated in the opposite direction. While within the stake pocket and without strap tension, the J-hook abuts the trailer frame and formation end wall and is, thereby, maintained within the pocket.

A side rail of a floor assembly of a trailer, such as a flatbed trailer, including a channel formed in a top wall of the side rail and an aperture formed in the top wall of the side rail at a location spaced-apart from the channel. The channel extends along a length of the side rail and is configured to receive a first cargo restraint device therein. The aperture is configured to receive a second cargo restraint device therein.

A fixture for attachment of an end of a member, such as a wind turbine tower section, blade or hub for a wind turbine characteristically has an end flange. To enable clamping while being able to compensate for different hole patterns in the flanges, by the invention, the fixture provides for retaining of ends of members with flanges, regardless of flange diameter and hole patterns, and which is also quickly and easily installed. Additionally, it is possible to firmly clamp the flange end to upstanding frame parts of the fixture with fastening elements, thereby providing a stable connection between a console of the fixture and the upstanding frame parts.

Method and apparatus for handling aerogenerator blades that provide a versatile means for handling aerogenerator blades without an unbalanced distribution of the loads in the blade. The method comprises positioning an upper mounting part (103) over the blade after the upper mold has been retracted; lifting the blade with the upper mounting part from the under mold using a lifting means; positioning the blade over an under mounting part (104) which is fixedly attached to an inferior movable support (102); attaching the upper mounting part to the under mounting part, wherein the upper and under mounting parts together have the inner surface substantially corresponding to the shape of the blade outer profile section. The invention further comprises an apparatus for handling aerogenerator blades.

A transport system for a wind turbine blade is provided. The transport system is configured for increasing a curvature of the wind turbine blade in response to an obstacle during transport of the wind turbine blade. Further, a method for transporting a wind turbine blade in order to avoid obstacles is provided.

An automatic lock affixed to a cargo container for interconnecting two stacked containers, and for automatically locking and unlocking without reliance upon the overcoming of a friction force to release the device.

A box stop device includes a base member and a raised member attached to the base member. The base member has a top surface and a bottom surface. The top surface may be flat. The bottom surface may be adapted to attach to a desired surface. The raised member may be attached to the base member and may extend approximately vertically from the top surface. The raised member may include a first side and a second side. The first side and the second side may be attached together at an angle of approximately 90 degrees.

A protective cap for a trailing edge of a rotor blade of a wind turbine for use during transportation, handling, or maintenance of the rotor blade is disclosed. The protective cap includes a body having a first leg, a second leg, and a cap member. The cap member connects the first and second legs. Further, the cap member may be configured to cover at least a portion of a trailing edge of the rotor blade and may be configured to provide a gap between an inner surface of the protective cap and the trailing edge. In addition, the first and second legs may resiliently engage the rotor blade.

An apparatus and method for providing a removable anchor for use in tying down a load, or for securing a winch cable for use in recovering a disabled vehicle or other load. The anchor may be removably attached to the deck/bed of a trailer or vehicle (e.g., a car carrier or wrecker/tow truck), using one or more slots or stake pockets located on a cargo surface of the deck. The removable anchor may include: a projection member shaped and sized to fit into a slot on the cargo surface, or to protrude through a stake pocket; a crown attached to, or integrally forming a part of, the projection member, and configured to receive and anchor one or more tie down connectors; and a key attached to, or integrally forming a part of, the projection member. The key can be passed into the slot and manipulated between removable and locked positions. Alternatively, the key may be used to removably secure the anchor to the stake pocket.

A module in the form of a pallet or a closed container includes a grouping together of the electrical devices in an avionics bay, in which the electrical devices are interconnected and attached so as to facilitate the mounting and thus limit the time it takes to mount the electrical devices in the avionics bay.

A cargo rack for transferring loads between a marine vessel and an offshore marine platform provides a frame having a front, a rear, and upper and lower end portions. The lower end of the frame has a perimeter beam base, a raised floor and a pair of open-ended parallel fork tine tubes that communicate with the perimeter beam at the front and rear of the frame. The frame includes a plurality of fixed side walls extending upwardly from the perimeter beam. A plurality of gates are movably mounted on the frame, each gate being movable between open and closed positions, the gates enabling a forklift to place loads on the floor. The frame has vertically extending positioning beams that segment the floor into a plurality of load-holding positions. Each load holding position has positioning beams that laterally hold a load module in position on the floor.

An apparatus for selectively securing a boat to a trailer may include a hull contact structure for abutting against the boat hull, and a releasable gripping structure positioned adjacent the hull contact structure to engage the boat's securing loop and selectively lock onto the loop to hold the boat to the trailer.

An apparatus and method for applying an underlayment layer to trucking cargo are provided. The underlayment layer may be formed into a roll with a rod disposed therethrough. The roll may be supported by a frame. The roll can be configured to move vertically with respect to the ground. A trailer carrying trucking cargo can be stationed beneath the frame. The underlayment layer may unwound and dispensed from the roll. In order to drape the trucking cargo with the underlayment layer, the roll may be moved horizontally over the frame in addition to or alternatively to having the trucking cargo driven horizontally with respect to the roll.

An anti-disassembling device for an electronic product includes a case, a linear movement device, a circular movement device and an optical encoder. At least one retractable transmission member is connected to the case. The circular movement device is located in the case and has an encoding disk, which has multiple slots defined therethrough and teeth are defined in the periphery thereof. The at least one retractable transmission member is engaged with the teeth to rotate the encoding disk. The optical encoder has a lighting module which emits light beams through the slots of the encoding disk and a photosensitive module receives the light beams and sends a signal to the storage unit of the electronic product. The retractable device rotates when the electronic product is disassembled.

A method for quickly calibrating a memory interface circuit from time to time in conjunction with operation of a functional circuit is described. The method uses controlling the memory interface circuit with respect to read data capture for byte lanes, including controlling CAS latency compensation for the byte lanes. In the method control settings for controlling CAS latency compensation are determined and set according to a dynamic calibration procedure performed from time to time in conjunction with functional operation of a circuit system containing one or more memory devices connected to the memory interface circuit. In the method, determining and setting the control settings for controlling CAS latency compensation is performed independently and parallely in each of the byte lanes.

A floorplan for a Structured ASIC chip is shown having a core region containing memory and VCLB logic cells surrounded by a plurality of IO connection fabrics that include a first IO connection fabric comprising IO sub-banks connecting the core of the chip to pins for external signals to the core, a first high-speed routing fabric disposed along the east-west vertical top of the core and connects the core to high-speed IO such as SerDes; a network-aware connection fabric connects the core to a microcontroller primarily for testing and repair of the memory in the core; and a second-high speed routing fabric is disposed on the north-south vertical sides of the core and communicates with the IO sub-banks. The VCLB Structured ASIC chip is manufactured on a 28 nm CMOS process lithographic node or smaller, having several metal layers and preferably is programmed on a single via layer.

Techniques for reducing scan overhead in a scannable flop tray are described herein. In one embodiment, a scan circuit for a flop tray comprises a tri-state circuit configured to invert an input data signal and output the inverted data signal to an input of a flip-flop of the flop tray in a normal mode, and to block the data signal from the input of the flip-flop in a scan mode. The scan circuit also comprises a pass gate configured to pass a scan signal to the input of the flip-flop in the scan mode, and to block the scan signal from the input of the flip-flop in the normal mode.

A device for passive equalization and slew-rate control of a signal includes a first branch and a second branch. The first branch includes a first driver coupled in series with an equalization capacitor. The second branch includes a second driver coupled in series with a resistor. The second branch may be coupled in parallel to the first branch. The first branch may be configurable to enable either passive equalization or slew-rate control of the signal based on a mode control signal.

Apparatus and methods are provided for an extraction circuit. In one configuration, an apparatus includes: an edge extraction circuit for receiving a first clock signal and outputting a second clock signal, wherein a duty cycle of the second clock is substantially smaller than a duty cycle of the first clock; a transistor for receiving the second clock signal and outputting a current signal; a transmission line for receiving the current signal on a first end and transmitting the current signal to a second end; a termination circuit for receiving the current signal at the second end and converting the current signal into a voltage signal; and an edge detection circuit for outputting a third clock by detecting an edge of the voltage signal. In one embodiment, the edge detection circuit comprises an inverter. In another embodiment, the edge detection circuit comprises a comparator.

A system and methods that generates a physical unclonable function (“PUF”) security key for an integrated circuit (“IC”) through use of equivalent resistance variations in the power distribution system (“PDS”) to mitigate the vulnerability of security keys to threats including cloning, misappropriation and unauthorized use.

A multi-chip package may include first and second integrated circuit dies that are each partitioned into multiple logic regions. The logic regions of the first and second dies may be coupled via interconnects. Each integrated circuit die may include at least one spare logic region. Multiple logic groups may be formed with each logic group including logic regions from the first and second integrated circuit dies and the interconnects that couple those logic regions. The logic groups may be evaluated to identify defective logic groups. In response to identifying a defective logic group, the defective logic group may be repaired by configuring the first and second integrated circuit dies to stop using the defective logic group and to use a spare logic group. The spare logic group may include spare logic regions of the first and second dies that are coupled by spare logic region interconnects.

An intelligent current drive is disclosed that couples an active current source to a bus line to increase the rate of pull-up and decouples the active current source from the bus line prior to reaching the desired pull-up voltage.

A method of configuring a programmable integrated circuit device with a user logic design includes analyzing the user logic design to identify unidirectional logic paths within the user logic design and cyclic logic paths within the user logic design, assigning the cyclic logic paths to logic in a first portion of the programmable integrated circuit device that operates at a first data rate, assigning the unidirectional logic paths to logic in a second portion of the programmable integrated circuit device that operates at a second data rate lower than the first data rate, and pipelining the unidirectional data paths in the second portion of the programmable integrated circuit device to compensate for the lower second data rate. A programmable integrated circuit device adapted to carry out such method may have logic regions operating at different rates, including logic regions with programmably selectable data rates.

An embodiment of this invention uses a massive parallel interconnect fabric (MPIF) at the flipped interface of a core die substrate (having the core logic blocks) and a context die (used for in circuit programming/context/customization of the core die substrate), to produce ASIC-like density and FPGA-like flexibility/programmability, while reducing the time and cost for development and going from prototyping to production, reducing cost per die, reducing or eliminating NRE, and increasing performance. Other embodiments of this invention enable debugging complex SoC through large contact points provided through the MPIF, provide for multi-platform functionality, and enable incorporating FGPA core in ASIC platform through the MPIF. Various examples are also given for different implementations.

A method and apparatus that controls the clock of a digital circuit, and therefore power consumption, without substantially comprising performance is provided. The apparatus may include monitoring the utilization of a First in First Out (FIFO) buffer. For example in a systems and methods according to the invention, clock speed may be reduced when the FIFO is relatively empty and increased when the FIFO is relatively full. The clock speed may be controlled by a phase locked loop, a clock divider, a clock masking device or a combination of more than one of these methods. Power reduction may also be obtained by controlling the clocking of different stages of a pipelined device. One or more aspects of the inventions may be implemented in combination with other aspects of the invention to further reduce power use.

Embodiments described herein provide approaches for improving a standard cell connection for circuit routing. Specifically, provided is an IC device having a plurality of cells, a first metal layer (M1) pin coupled to a contact bar extending from a first cell of the plurality of cells, and a second metal layer (M2) wire coupled to the contact bar, wherein the contact bar extends across at least one power rail. By extending the contact bar into an open area between the plurality of cells to couple the M1 pin and the M2 wire, routing efficiency and chip scaling are improved.

The present invention relates to a method for downloading a binary configuration file in a programmable circuit implemented in a device. The device comprises at least one central processing unit, a plurality of connectors, and a programmable circuit enabling all or a part of the signals received by said connectors to be processed and transmitted to at least one other circuit of the device. The device analyzes the signals present on the connectors in order to define what other devices are connected and whether the connections are operational. Then, a configuration file is selected from among a set of configuration files according to the operational connections and is downloaded from a memory of the device into the programmable circuit. The invention also relates to a device having a component programmed according to the method previously described.

The present disclosure relates to nanoresonator oscillators or NEMS (nanoelectromechanical system) oscillators. A circuit for measuring the oscillation frequency of a resonator is provided, comprising a first phase-locked feedback loop locking the frequency of a controlled oscillator at the resonant frequency of the resonator, this first loop comprising a first phase comparator. Furthermore, a second feedback loop is provided which searches for and stores the loop phase shift introduced by the resonator and its amplification circuit when they are locked at resonance by the first loop. The first and the second loops operate during a calibration phase. A third self-oscillation loop is set up during an operation phase. It directly links the output of the controllable phase shifter to the input of the resonator. The phase shifter receives the phase-shift control stored by the second loop.

An integrated circuit (10) has an internal RC-oscillator (20) for providing an internal clock signal (CLI) having an adjustable oscillator frequency. The integrated circuit (10) further comprises terminals (101, 102) for connecting an external LC tank (30) having a resonance frequency and a calibration circuit (40) which is configured to adjust the oscillator frequency based on the resonance frequency of the LC tank (30) connected during operation of the integrated circuit (10). An internal auxiliary oscillator (46) is connected to the terminals (101, 102) in a switchable fashion and is configured to generate an auxiliary clock signal (CLA) based on the resonance frequency. The calibration circuit (40) comprises a frequency comparator (47) which is configured to determine a trimming word (TRW) based on a frequency comparison of the internal clock signal (CLI) and the auxiliary clock signal (CLA). The LC tank (30) to be connected is an antenna for receiving a radio signal.

The invention concerns an oscillator generating a wave composed of a frequency of on the order of terahertz from a beat of two optical waves generated by a dual-frequency optical source. The oscillator includes a modulator the transfer function of which is non-linear for generating harmonics with a frequency of less than one terahertz for each of the optical waves generated by the dual-frequency optical source, an optical detector able to detect at least one harmonic for each of the optical waves generated by the dual-frequency optical source and transforming the harmonics detected into an electrical signal, a phase comparator for comparing the electrical signal with a reference electrical signal, and a module for controlling at least one element of the dual-frequency optical source with a signal obtained from the signal resulting from the comparison.

An oscillator module includes a first MOS transistor and a capacitor. The capacitor is coupled between a gate and source of the first MOS transistor. The drain of the first MOS transistor receives a first bias current and generates an oscillating output signal. A switching circuit operates in response to the oscillating output signal to selective charge and discharge the capacitor. A current sourcing circuit is configured to generate the bias current. The current sourcing circuit includes a second MOS transistor which has an identical layout to the first MOS transistor and receives a second bias current. A resistor is coupled between a gate and source of the second MOS transistor. The current sourcing circuit further includes a current mirror having an input configured to receive a reference current passing through the resistor and generate the first and second bias currents.

An integrated structure of compound semiconductor devices is disclosed. The integrated structure comprises from bottom to top a substrate, a first epitaxial layer, an etching-stop layer, a second epitaxial layer, a sub-collector layer, a collector layer, a base layer, and an emitter layer, in which the first epitaxial layer is a p-type doped layer, the second epitaxial layer is an n-type graded doping layer with a gradually increased or decreased doping concentration, and the sub-collector layer is an n-type doped layer. The integrated structure can be used to form an HBT, a varactor, or an MESFET.

Systems and methods for switching impedance are provided. In some aspects, a system includes first and second impedance elements and an impedance switch module, which includes a third impedance element coupled between the first and second impedance elements and a switch parallel to the third impedance element. The switch is coupled between the first and second impedance elements, and is configured to switch between an open configuration and a closed configuration. An electrical path is completed between the first impedance element and the second impedance element via the first switch in the closed configuration. The electrical path is not completed in the open configuration. A total impedance of the first impedance element, the second impedance element, and the impedance switch module is varied based on the switching between the open configuration and the closed configuration.