Abstract: Circuits are provided for synchronizing serial communication channels having respective receivers, of which one is a master receiver. Each receiver includes a FIFO buffer and a synchronizing element. The FIFO buffer is written periodically with characters received from the serial communication channel of the receiver, and the FIFO buffer is read periodically, except between the start and end of synchronization of the receiver. The start of synchronization of the master receiver is generated from the timing of reading a channel bonding character from the FIFO buffer of the master receiver. The start of synchronization of each receiver other than the master receiver is generated after the start of the master receiver and in response to reading a channel bonding character from the FIFO buffer of the receiver. The end of synchronization of the receivers is generated a time interval after the start of the master receiver.
Abstract: An embodiment of a technique to transfer data between two different interfaces is disclosed. The embodiment of the technique includes: manipulating data arriving at a first data interface with a first word width into data with a second word width; transferring the manipulated data to a second data interface having the second word width; and selecting one of a plurality of different word widths for one of the first or second word widths.
Type:
Grant
Filed:
January 19, 2010
Date of Patent:
August 7, 2012
Assignee:
Xilinx, Inc.
Inventors:
Wayne E. Wennekamp, Adam Elkins, Schuyler E. Shimanek, Steven E. McNeil
Abstract: An embodiment of a circuit is described that includes a first inductor comprising a first end and a second end, where the first end of the first inductor forms an input node of the circuit. The embodiment of the circuit further includes a second inductor comprising a first end and a second end, where the second end of the first inductor is coupled to the first end of the second inductor forming an output node of the circuit; a resistor coupled to the second end of the second inductor; and an electrostatic discharge structure coupled to the output node and configured to provide an amount of electrostatic discharge protection, where the amount of electrostatic discharge protection is based on a parasitic bridge capacitance and a load capacitance metric.
Type:
Application
Filed:
April 6, 2012
Publication date:
July 26, 2012
Applicant:
Xilinx, Inc.
Inventors:
Vassili Kireev, James Karp, Toan D. Tran
Abstract: An electronic assembly includes a substrate having bond pads on a surface of the substrate. A solder mask covers the surface of the substrate, and a solder connection is disposed on each of the bond pads. At least one trench is formed in the solder mask, and is located between adjacent ones of the bond pads. At least one component has contact pads, and each contact pad is connected to one of the bond pads via one of the solder connections. The trench is located beneath the device and extends at least from one edge of the device to a location underneath the device. Underfill material fills the trench and space between the solder mask and the device.
Abstract: Method and apparatus for modeling processor-based circuit models are described. Some examples relate to designing a circuit model having a processor system and custom logic. A bus adapter coupled to a bus of the processor system is generated. A shared memory interface between the custom logic and the bus adapter is generated. The shared memory interface includes a memory map for the processor system. A clock wrapper having a first clock input and a second clock input is generated. The first clock input drives the custom logic and first shared memory of the shared memory interface. The second clock input drives the processor system.
Type:
Grant
Filed:
September 29, 2008
Date of Patent:
July 24, 2012
Assignee:
Xilinx, Inc.
Inventors:
Jingzhao Ou, Chi Bun Chan, Shay Ping Seng
Abstract: A method of accepting a sample of an input signal to be used to calculate parameters for a predistortion circuit in an integrated circuit is disclosed. The method comprises accumulating data associated with an input signal over a period of time; detecting the sample of the input signal at a predetermined time; comparing the sample of the input signal to the accumulated data; and determining whether the sample of the input signal is acceptable to be used to calculate parameters for the predistortion circuit. A circuit for accepting a sample of an input signal to be used to calculate parameters for a predistortion circuit in an integrated circuit is also disclosed.
Abstract: A biasing circuit of an integrated circuit includes a well of the integrated circuit and a plurality of transistors disposed in the well. The transistors couple the well to three signals providing corresponding voltages. The transistors bias the well to an extreme one of the corresponding voltages for the three signals.
Abstract: A computer-implemented method of globally placing a circuit design on a programmable integrated circuit (IC) includes dividing, by a placement system, the programmable IC into a grid comprising a plurality of cells, assigning each component of a selected component type of the circuit design to one of a plurality of control set groups according to a control set of the component, and calculating a force including a control set force that depends upon overlap of control sets within the plurality of cells. The method further can include applying the force to at least one selected component of the circuit design and assigning components of the circuit design to locations on the programmable IC by solving a set of linear equations that depend upon application of the force to the at least one selected component to create a global placement. The circuit design including the global placement can be output.
Abstract: In one embodiment, a monitor circuit is disclosed. For example, the monitor circuit includes a first delay line circuit having a plurality of delay taps for receiving data from a data channel, and a second delay line circuit having a plurality of points for sampling the data received from the first delay line circuit, where the plurality of points comprises an input point, a middle point and an output point. The monitor circuit further includes a voltage control circuit for providing a control voltage to the second delay line circuit, and a data compare circuit for comparing a data value of the input point and a data value of the middle point to produce a first out-of-bounds signal, and for comparing the data value of the middle point and a data value of the output point to produce a second out-of-bounds signal.
Abstract: In one embodiment, a device is disclosed. For example, in one embodiment of the present invention, the device comprises a memory core having a shared buffer, and an arbitration logic module for receiving a destination ready signal from a processing source of a plurality of processing sources. The device also comprises at least one pipeline stage for storing at least one piece of data read from the shared buffer, and at least one matching pipeline stage storing at least one valid signal associated with the at least one piece of data read from the shared buffer. The device also comprises a counter for storing a value, wherein the value represents a number of pieces of data read from the shared buffer, but have not been delivered to the processing source.
Abstract: An integrated circuit can include a processor system configured to execute program code, wherein the processor system is hard-wired. The IC also can include programmable circuitry configurable to implement different physical circuits. The programmable circuitry can be coupled to the processor system and can be configured to implement a power off procedure under the control of the processor system.
Type:
Application
Filed:
January 13, 2011
Publication date:
July 19, 2012
Applicant:
Xilinx, Inc..
Inventors:
Bradley L. Taylor, Ting Lu, William E. Allaire, Hassan K. Bazargan, Hy V. Nguyen, Shashank Bhonge
Abstract: A method of extending a processor system within an integrated circuit (IC) can include executing program code within the processor system implemented within the IC, wherein the IC includes a programmable fabric. The processor system further can be coupled to the programmable fabric. A process can be performed using a process-specific circuit implemented within the programmable fabric in lieu of using the processor system. A result of the process from the process-specific circuit can be made available to the processor system.
Abstract: An aspect of the invention relates to modeling a transistor in an integrated circuit design. Layout data for the integrated circuit design is obtained. A geometry relating the transistor to at least one well edge of at least one implant well is extracted from the layout data. An effective well proximity value for the transistor is calculated based on the at least one well edge using a complementary error function. The transistor is modeled using the effective well proximity value. In one embodiment, the effective well proximity value is added to a post-layout extracted netlist for the integrated circuit design. The integrated circuit design may be simulated using the post-layout extracted netlist. The effective well proximity value may be used to calculate a threshold voltage for the transistor during the step of simulating the integrated circuit.
Type:
Grant
Filed:
April 2, 2007
Date of Patent:
July 17, 2012
Assignee:
Xilinx, Inc.
Inventors:
Jane W. Sowards, Shuxian Wu, Kaiman Chan
Abstract: A method and apparatus to reduce the degradation in performance of semiconductor-based devices due to process, voltage, and temperature (PVT) and/or other causes of variation. Adaptive feedback mechanisms are employed to sense and correct performance degradation, while simultaneously facilitating configurability within integrated circuits (ICs) such as programmable logic devices (PLDs). A voltage-feedback mechanism is employed to detect PVT variation and mirrored current references are adaptively adjusted to track and substantially eliminate the PVT variation. More than one voltage-feedback mechanism may instead be utilized to detect PVT-based variations within a differential device, whereby a first voltage-feedback mechanism is utilized to detect common-mode voltage variation and a second voltage-feedback mechanism produces mirrored reference currents to substantially remove the common-mode voltage variation and facilitate symmetrical operation of the differential device.
Abstract: A method of managing programmable device configuration can include running a server configuration image within the programmable device and storing a different configuration image within a non-volatile memory communicatively linked with the programmable device. Responsive to a switch request sent from the client to the programmable device over the communications link, the different configuration image can be loaded into the programmable device.
Type:
Grant
Filed:
January 5, 2007
Date of Patent:
July 17, 2012
Assignee:
Xilinx, Inc.
Inventors:
Nabeel Shirazi, Chi Bun Chan, Bradley K. Fross, Shay Ping Seng, Jonathan B. Ballagh
Abstract: A technique is provided for memory control in a device having programmable circuitry, including providing a dedicated memory controller circuit in the device before the programmable circuitry is field programmed. Another technique involves fabricating a device, where the fabricating involves forming programmable circuitry that includes a dedicated memory controller circuit before the circuitry is field programmed.
Type:
Grant
Filed:
January 27, 2010
Date of Patent:
July 17, 2012
Assignee:
Xilinx, Inc.
Inventors:
Schuyler E. Shimanek, Wayne E. Wennekamp, Joe E. Leyba, Adam Elkins, Thomas H. Strader, Chidamber R. Kulkarni, Mikhail A. Wolf, Steven E. McNeil
Abstract: A method of placing clock circuits in an integrated circuit is disclosed. The method comprises receiving a circuit design to be implemented in the integrated circuit; identifying portions of the circuit design comprising clock circuits; determining an order of clock circuits to be placed based upon resource requirements of the clock circuits; and placing the portions of the circuit design comprising clock circuits in sites of the integrated circuit. A system for placing clock circuits in an integrated circuit is also disclosed.
Type:
Grant
Filed:
March 18, 2009
Date of Patent:
July 17, 2012
Assignee:
Xilinx, Inc.
Inventors:
Marvin Tom, Wei Mark Fang, Srinivasan Dasasathyan
Abstract: Integrated circuits for an output driver and an output interface, as well as a method for operating an output driver, are described. In an embodiment of an integrated circuit for an output driver, a differential driver is coupled to a first single-ended driver at a first output node of the first single-ended driver and the differential driver. A second single-ended driver is coupled to the differential driver at a second output node of the second single-ended driver and the differential driver. The first single-ended driver provides a first source termination resistance for an open-drain mode of the differential driver, and the second single-ended driver provides a second source termination resistance for the open-drain mode of the differential driver.
Abstract: A cyclic redundancy check (CRC) bit-slice circuit including a plurality of AND gates coupled with configuration data is described. The configuration data may enable the plurality of AND gates to provide a set of CRC input data and feedback polynomial data meeting a plurality of CRC protocols. The CRC bit-slice circuit accepts a generator polynomial as an input design parameter to build a CRC module. The modularity of the design then allows a larger CRC design to be constructed from multiple CRC modules such that wider data width may be accommodated. Several CRC modules can be cascaded to accommodate various data widths and to meet a plurality of CRC protocols.
Type:
Grant
Filed:
March 31, 2008
Date of Patent:
July 17, 2012
Assignee:
Xilinx, Inc.
Inventors:
David P. Schultz, Christopher D. Ebeling
Abstract: In one embodiment, a method is provided for generating clock gating circuitry for a circuit design model. A Boolean expression of path sensitization is determined for each gate element in the netlist of a circuit design. For each gate element, a conjunction of the Boolean expression of the path sensitization and a Boolean expression of a disjunction of the observability conditions of one or more subsequent gates is determined to produce an intermediate Boolean expression. Intermediate Boolean expressions are backward retimed to produce the respective Boolean expression of the observability conditions of the each gate element. Clock gating circuits that implement the respective Boolean expression of the observability conditions of one or more of the plurality of interconnected gate elements are generated and incorporated into the circuit design model.