Patents Assigned to Xilinx, Inc.
  • Patent number: 9377795
    Abstract: In an example, a temperature-corrected voltage reference circuit for use in an integrated circuit (IC) includes a voltage reference circuit, a programmable gain amplifier, and a digital control circuit. The programmable gain amplifier includes a first input coupled to the voltage reference circuit, a second input coupled to receive a control signal, and an output coupled to provide a temperature-corrected voltage reference. The digital control circuit includes an input coupled to receive a temperature signal indicative of temperature of the IC and an output coupled to the second input of the programmable gain amplifier, the digital control circuit generating the control signal in response to the temperature signal.
    Type: Grant
    Filed: November 17, 2014
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Ionut C. Cical, Edward Cullen
  • Patent number: 9378102
    Abstract: A system on a chip (SoC) for providing safety hardware fault tolerance and/or safety software fault tolerance includes a first safety sub-system having a first safety channel; a second safety sub-system having a second safety channel; and a third sub-system. The first safety sub-system is independent of the second safety sub-system to allow the second safety sub-system to communicate through the second safety channel when the first safety sub-system or the third subsystem fails, and further to allow the first safety sub-system to communicate through the first safety channel when the second safety sub-system or the third subsystem fails.
    Type: Grant
    Filed: August 6, 2014
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Sagheer Ahmad, Bradley L. Taylor, Giulio Corradi
  • Patent number: 9377802
    Abstract: In one embodiment, an integrated circuit (IC) includes a power distribution network having a first set of power distribution lines connected to a source voltage and a second set of power distribution lines connected to a ground voltage, and a first capacitor. A first variable resistive element is electrically coupled in series with the first capacitor between the first and second sets of power lines of the power distribution network. A control circuit is coupled to the variable resistive element and is configured and arranged to adjust a level of resistance of the first variable resistive element in response to an input signal. The adjustment of the level of resistance adjusts an equivalent series resistance of the power distribution network.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Christopher P. Wyland, Romi Mayder, Paul Y. Wu
  • Patent number: 9378170
    Abstract: An apparatus relating generally to encoding is disclosed. This apparatus includes a bus interface for communicating information from a first die including the bus interface to a second die. A first portion of a bus associated with the bus interface is associated with data bits. A second portion of the bus associated with the bus interface is associated with encoding bits. The bus interface is configured to encode a data word to provide an encoded word. The encoded word is associated with a combinatorial number system.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventor: Ephrem C. Wu
  • Patent number: 9378322
    Abstract: According to a method of preparing a layout of semiconductor circuit elements, a computer processor determines a first value of a distance metric that describes a separation between at least one well of a first type and at least one well of a second type in a first layout of a circuit design represented in a memory coupled to the computer processor. The at least one well of the first type and the at least one well of the second type are rearranged into a second layout. The method determines a second value of the distance metric that describes separation between the at least one well of the first type and the at least one well of the second type in the second layout. The second layout is stored in response to the second value of the distance metric being greater than the first value of the distance metric.
    Type: Grant
    Filed: January 23, 2015
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventor: James Karp
  • Patent number: 9378174
    Abstract: An apparatus relates generally to serializer-deserializers. In such an apparatus, a first serializer-deserializer has a first data path and a data eye path. The first data path is coupled to a first data out interface of the first serializer-deserializer. A second serializer-deserializer has a second data path. The second data path is coupled to a second data out interface of the second serializer-deserializer. The data eye path of the first serializer-deserializer is coupled to the second data path of the second serializer-deserializer.
    Type: Grant
    Filed: November 4, 2013
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Paolo Novellini, Anthony Torza
  • Patent number: 9379109
    Abstract: An integrated circuit device having improved radiation immunity is described. The integrated circuit device comprises an n-type wafer having a first surface and a second surface; a p-type epitaxial layer formed on the first surface of the n-type wafer, the p-type epitaxial wafer having first elements storing charge; and an n-well formed in the p-type epitaxial layer, the n-well having second elements storing charge; wherein the n-type wafer is positively biased to attract excess minority carriers in the p-type epitaxial layer. A method of improving radiation immunity in an integrated circuit is also described.
    Type: Grant
    Filed: April 4, 2012
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: James Karp, Michael J. Hart
  • Patent number: 9379663
    Abstract: In one example, an oscillator circuit includes: a master oscillator comprising a master LC tank coupled to a master active circuit, the master LC tank including a primary winding of a transformer and a capacitance; a slave oscillator comprising a slave LC tank coupled to a slave active circuit, the slave LC tank including a secondary winding of the transformer and a capacitance; and a first pair of coupling transistors and a second pair of coupling transistors each coupling the master oscillator to the slave oscillator. Gates of the first pair of coupling transistors are coupled to the master oscillator through a switch. Gates of the second pair of coupling transistors are coupled to the master oscillator through respective ninety-degree phase shifters and the switch.
    Type: Grant
    Filed: March 23, 2015
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Somnath Kundu, Vassili Kireev
  • Patent number: 9379880
    Abstract: Clock data recovery can be accomplished using a phase change determination circuit that generates, based upon detected phase differences between a capture clock signal and data signal, a delta signal and a delta selection signal. A calculation circuit generates a set of phase interpolation (PI) codes from prior and speculative values of the delta signal. A selection circuit selects, in response to the delta selection signal, between the sets of PI codes, which are provided as an output of the clock data recovery device.
    Type: Grant
    Filed: July 9, 2015
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Yu Xu, Yohan Frans, Kun-Yung Chang
  • Patent number: 9379720
    Abstract: Clock data recovery can be accomplished using a phase path circuit that is configured to receive a data signal and a clock signal. A phase detection circuit detects phase differences between the data signal and a plurality of clock signals and generates a phase adjustment signal based upon a majority voting of the detected phase differences. Speculative calculation circuits generate speculative phase selection signals. Selection circuits select, in response to the phase adjustment signal, from speculative phase selection signals to provide outputs of the phase path circuit.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Yu Xu, Santiago G. Asuncion, Tianqi Tang, Toan Pham, Kun-Yung Chang
  • Patent number: 9378003
    Abstract: Approaches for generating and operating an electronic system. High-level language (HLL) source code is compiled into equivalent intermediate language program code. The compilation determines a plurality of caches for storing data referenced by the HLL source. Flush instructions are inserted in the intermediate language program. Each flush instruction references one of caches and is inserted in the intermediate language program immediately following an instruction that is last to write to that cache. The intermediate language program is translated into a hardware description that specifies the plurality of caches, circuits for processing data in the caches, and for each of the caches a flush interface that initiates writing data from the cache to a main memory in response to a flush signal. The timing of the respective flush signal is determined based on placement of one of the one or more flush instructions in the intermediate language program.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Prasanna Sundararajan, Andrew R. Putnam, Jeffrey M. Mason
  • Patent number: 9379920
    Abstract: In a receiver, a decision feedback equalizer (“DFE”) receives an analog input signal. The DFE includes a subtraction block for subtracting weighted postcursor decisions from an analog input signal to provide an analog output signal. A postcursor decision block coupled to the DFE compares the analog output signal against positive and negative values of a postcursor coefficient to provide first and second possible decisions for selecting a current postcursor-based decision therebetween responsive to a previous postcursor-based decision. A precursor cancellation block receives the analog output signal, the previous postcursor-based decision and the current postcursor-based decision for providing a digital output signal for a previous sample of the analog input signal.
    Type: Grant
    Filed: May 8, 2015
    Date of Patent: June 28, 2016
    Assignee: XILINX, INC.
    Inventors: Yu Liao, Hongtao Zhang, Kun-Yung Chang, Geoffrey Zhang
  • Patent number: 9372948
    Abstract: Techniques for using a speed measurement circuit to measure speed of an integrated circuit. The speed measurement circuit includes a ring oscillator and a counter circuit. The ring oscillator includes an AND gate with an inverting input and a non-inverting input. The ring oscillator also includes a programmable interconnect point context (PIP-context) having a first programmable interconnect point (PIP), a first interconnect, a second PIP, and a second interconnect coupled in series. The ring oscillator also includes a third interconnect and a third PIP coupled in series with the PIP-context and with an inverting input of the AND gate. The counter circuit is coupled to an output of the AND gate and configured in the programmable integrated circuit.
    Type: Grant
    Filed: June 4, 2015
    Date of Patent: June 21, 2016
    Assignee: XILINX, INC.
    Inventor: Nagaraj Savithri
  • Patent number: 9372956
    Abstract: A method of enabling the use of a programmable device having impaired circuitry includes determining one or more locations of the impaired circuitry of the programmable device; generating a defect map for the programmable device based on the determined locations of the impaired circuitry; generating a plurality of configuration bitstreams to implement a circuit in the programmable device; selecting one of the plurality of configuration bitstreams that does not use the impaired circuitry indicated by the defect map; and programming the programmable device with the selected configuration bitstream.
    Type: Grant
    Filed: November 10, 2014
    Date of Patent: June 21, 2016
    Assignee: XILINX, INC.
    Inventors: Yuezhen Fan, Eric J. Thorne, Xiao-Yu Li, Glenn O'Rourke, Stephen M. Trimberger
  • Patent number: 9372953
    Abstract: Processing a circuit design includes determining that an operating frequency for a first placement and routing for the circuit design does not exceed a target operating frequency, distinguishing between loop paths and feed-forward paths in the circuit design, and, responsive to determining that the operating frequency does not exceed the target operating frequency, relaxing timing constraints of the feed-forward paths using a processor. A second placement and routing is performed on the loop paths and the feed-forward paths of the circuit design.
    Type: Grant
    Filed: September 24, 2014
    Date of Patent: June 21, 2016
    Assignee: XILINX, INC.
    Inventors: Shant Chandrakar, Ilya K. Ganusov
  • Publication number: 20160164558
    Abstract: An apparatus relates generally to providing a divided signal output. In such an apparatus, a controller is coupled to receive a reference frequency count and a feedback frequency count to determine a difference therebetween to provide a control setting. A divider is coupled to receive the control setting to provide the divided signal output. The divider includes an adjustable load impedance. The control setting is coupled to adjust the load impedance of the divider to adjust a self-resonance frequency of the divider.
    Type: Application
    Filed: December 5, 2014
    Publication date: June 9, 2016
    Applicant: XILINX, INC.
    Inventor: Mohamed N. Elzeftawi
  • Publication number: 20160164665
    Abstract: In a method for buffering, a buffer buffers data responsive to read and write clock signals. A flag signal from the buffer is for a fill level thereof. The flag signal is toggled responsive to the data buffered being either above or below a set point for the fill level. A phase of the write clock signal is adjusted to a phase of the read clock signal responsive to the toggling of the flag signal. The write clock signal is used to control latency of the buffer. The adjusting of the phase of the write clock signal includes: generating an override signal responsive to the toggling of the flag signal; and inputting the read clock signal and the override signal to a phase adjuster to controllably adjust the phase of the write clock signal to the phase of the read clock signal during operation.
    Type: Application
    Filed: December 5, 2014
    Publication date: June 9, 2016
    Applicant: XILINX, INC.
    Inventors: David F. Taylor, Matthew H. Klein, Vincent Vendramini
  • Patent number: 9355696
    Abstract: In an example, a control device includes a data path, a clock path, a multiplexing circuit, and a calibration unit. The data path comprises a data delay unit coupled to a data input of a sampling circuit. The clock path comprises a clock delay unit coupled to a clock input of the sampling circuit. The multiplexing circuit selectively couples a reference clock or a data bus to an input of the data delay unit, and selectively couples the reference clock or a source clock to an input of the clock delay unit. The calibration unit is coupled to a data output of the sampling circuit. The calibration unit is operable to adjust delay values of the data delay unit and the clock delay unit based on the data output of the sampling circuit to establish and maintain a relative delay between the data path and the clock path.
    Type: Grant
    Filed: November 6, 2014
    Date of Patent: May 31, 2016
    Assignee: XILINX, INC.
    Inventors: Terence J. Magee, Xiaoqian Zhang
  • Patent number: 9356556
    Abstract: A circuit for implementing a dual-mode oscillator is disclosed. The circuit comprises a first oscillator portion having a first inductor coupled in parallel with a first capacitor between a first node and a second node; a first pair of output nodes coupled to the first and second nodes; a second oscillator portion inductively coupled to the first oscillator portion, the second oscillator portion having a second inductor coupled in parallel with a second capacitor between a third node and a fourth node; a second pair of output nodes coupled to the third and fourth nodes; and a control circuit coupled to enable a supply of current to either the first oscillator portion or the second oscillator portion. A method of implementing a dual-mode oscillator is also disclosed.
    Type: Grant
    Filed: August 6, 2015
    Date of Patent: May 31, 2016
    Assignee: XILINX, INC.
    Inventors: Mayank Raj, Parag Upadhyaya
  • Patent number: 9356775
    Abstract: Methods and apparatus are described for synchronously stepping at least one of a data phase interpolator (PI) code or a crossing PI code in a clock and data recovery (CDR) circuit until one or more preset criteria are satisfied. One example method generally includes determining that a condition has been met; based on the determination, stepping, in a CDR circuit, at least one of a data PI code or a crossing PI code for each cycle of a clock; stopping the stepping based on one or more criteria to generate a predetermined state of the data PI code and the crossing PI code, wherein the predetermined state comprises an offset between the data PI code and the crossing PI code; receiving a data stream; and performing clock and data recovery on the data stream based on the offset between the data PI code and the crossing PI code.
    Type: Grant
    Filed: July 9, 2015
    Date of Patent: May 31, 2016
    Assignee: XILINX, INC.
    Inventors: Yu Xu, Cheng-Hsiang Hsieh, Yohan Frans, Kun-Yung Chang