Two Or More Clocks (e.g., Phase Clocking, Etc.) Patents (Class 326/96)
  • Patent number: 7902877
    Abstract: A multiphase clock generates pulses at a rate much higher than the clock frequency.
    Type: Grant
    Filed: January 6, 2010
    Date of Patent: March 8, 2011
    Assignee: ESS Technology, Inc.
    Inventors: Dustin D. Forman, Andrew Martin Mallinson
  • Patent number: 7893722
    Abstract: State storage circuitry is described comprising a master-slave latch having tristate inverter circuitry 2 at its functional input and tristate scan signal insertion circuitry 12 for inserting scan data. The tristate scan signal insertion circuitry 12 is controlled by a first clock signal nclk and a second clock signal bclk. The tristate inverter circuitry 2 is controlled by a third clock signal nfclk and a fourth clock signal flck. The clock generating circuitry holds the third and fourth clock signals at fixed values which tristate the tristate inverter circuitry 2 when in scan mode. This moves scan control logic out of the function path comprising the tristate inverter circuitry into the clock control circuitry.
    Type: Grant
    Filed: September 11, 2008
    Date of Patent: February 22, 2011
    Assignee: ARM Limited
    Inventors: Stephen Andrew Kvinta, Marlin Wayne Frederick, Chih-Wei Huang
  • Patent number: 7882473
    Abstract: Mechanisms for performing sequential equivalence checking for asynchronous verification are provided. A first model of the integrated circuit design is provided that has additional logic in it to reflect the possible variance in behavior of the asynchronous crossings. A second model of the integrated circuit design is provided that does not have this asynchronous behavior logic but instead correlates to the simplest synchronous model that is usually used for non-asynchronous functional verification tasks. Sequential equivalence checking is performed to verify that the two models are input/output equivalent. In order to address non-uniform arrival times of bus strands, logic is provided for identifying bus strands that have transitioning bits, determining a representative delay for these strands, comparing the representative delays for all of the bus strands to determine the maximum delay for the entire bus, and applying this maximum delay to one of the models.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: February 1, 2011
    Assignee: International Business Machines Corporation
    Inventors: Jason R. Baumgartner, Yee Ja, Hari Mony, Viresh Paruthi, Barinjato Ramanandray
  • Patent number: 7852707
    Abstract: A semiconductor memory device using system clock with a high frequency can maintain a constant margin of operation even with a changed operating environment including voltage level, temperature, and process. The semiconductor memory device includes a data output control circuit configured to control data outputted in synchronization with a falling edge of a system clock using a first output source signal corresponding to a rising edge of the system clock, and to control data outputted in synchronization with the rising edge of the system clock using a second output source signal corresponding to a falling edge of the system clock, and a data output circuit configured to output data, the data output circuit being controlled by the data output control circuit.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: December 14, 2010
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hee-Jin Byun
  • Patent number: 7825696
    Abstract: The even-number-stage pulse delay includes a ring delay line constituted of an even number of inverter circuits connected in a ring around which main edge and a reset edge circulate together. The even-number-stage pulse delay is provided with an operation monitoring section configured to detect whether or not the main and reset edges are circulating around the ring delay line.
    Type: Grant
    Filed: December 16, 2009
    Date of Patent: November 2, 2010
    Assignee: Denso Corporation
    Inventors: Takamoto Watanabe, Shigenori Yamauchi
  • Patent number: 7808276
    Abstract: Embodiments of the invention relate to a chip-to-chip communication system including a transmitter and a receiver connected to receive respective transmitter and receiver clock signals. The transmitter includes precharge and evaluation blocks connected to each other and to a transmitter clock terminal. The receiver includes a precharge block connected to a receiver clock terminal. The precharge blocks precharge an output terminal of the transmitter and an input terminal of the receiver, respectively, to a value corresponding to a first voltage reference during a low phase of the transmitter clock signal.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: October 5, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Luca Ciccarelli, Luca Magagni, Alberto Fazzi, Roberto Canegallo, Roberto Guerrieri
  • Patent number: 7746117
    Abstract: A complementary energy path adiabatic logic (CEPAL) includes an evaluation network and a power clock network. The evaluation network is a logic circuit composed of P-type MOS transistors and N-type MOS transistors. The power clock network includes a P-type and N-type MOS transistors and additional P-type and N-type MOS transistors, with each of the transistors involved in the power clock network acting as an active diode.
    Type: Grant
    Filed: September 24, 2008
    Date of Patent: June 29, 2010
    Assignee: Chang Gung University
    Inventors: Ci-Tong Hong, Cihun-Siyong Gong, Chun-Hsien Su, Muh-Tian Shiue, Kai-Wen Yao
  • Publication number: 20100156467
    Abstract: A control system includes a clock unit for providing a first clock signal, and a second clock signal having a frequency lower than that of the first clock signal. Three control units are coupled respectively to three light emitting diodes (LED) emitting respectively three different colors. Each control unit is operable based on the clock signals and a corresponding set of first and second reference values to output a driving pulse signal to a corresponding LED such that the corresponding LED is driven by the driving pulse signal to emit light during a corresponding one of first, second and third time periods of a control cycle of the control system.
    Type: Application
    Filed: December 18, 2008
    Publication date: June 24, 2010
    Applicant: National Chi Nan University
    Inventors: Tai-Ping Sun, Chia-Hung Wang, Tzu-Lun Hung, Heng-Yu Yan
  • Patent number: 7733130
    Abstract: A data communications system is disclosed. The data communications system comprises two clock domains. Each of the clock domains are coupled to receive a source clock signal. The first clock domain includes a first clock signal and the second clock domain includes a second clock signal, each of the first clock signal and the second clock signal are derived from the source clock signal. The first clock signal has a frequency which is different from that of the second clock signal. The system includes circuitry configured to generate a pulse indicative of when data transferred between the first clock domain and the second clock domain may be latched. Data is only latched when the pulse is asserted and on a given edge of the first clock signal, and the circuitry is configured to generate the pulse such that the given edge occurs at approximately a position corresponding to a middle of a period of the second clock signal.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: June 8, 2010
    Assignee: Oracle America, Inc.
    Inventors: Mahmudul Hassan, Tzungren Allan Tzeng
  • Patent number: 7725756
    Abstract: A method for generating a wide range of clock rates from a single clock. A delta is generated from a first clock signal and a second clock signal. An accumulative offset is generated from adding the delta to a previous accumulative offset for each clock period of the first clock signal. Whenever an overflow is encountered, the value of the accumulative offset is truncated. The second clock signal is interpolated between adjacent values.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: May 25, 2010
    Assignee: GoBack TV, Inc.
    Inventors: Javier Solis, Xuduan Lin, Michael Field
  • Publication number: 20100109708
    Abstract: An object is to apply a transistor using an oxide semiconductor to a logic circuit including an enhancement transistor. The logic circuit includes a depletion transistor 101 and an enhancement transistor 102. The transistors 101 and 102 each include a gate electrode, a gate insulating layer, a first oxide semiconductor layer, a second oxide semiconductor layer, a source electrode, and a drain electrode. The transistor 102 includes a reduction prevention layer provided over a region in the first oxide semiconductor layer between the source electrode and the drain electrode.
    Type: Application
    Filed: October 26, 2009
    Publication date: May 6, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Jun KOYAMA, Kengo AKIMOTO, Masashi TSUBUKU
  • Publication number: 20100060321
    Abstract: State storage circuitry is described comprising a master-slave latch having tristate inverter circuitry 2 at its functional input and tristate scan signal insertion circuitry 12 for inserting scan data. The tristate scan signal insertion circuitry 12 is controlled by a first clock signal nclk and a second clock signal bclk. The tristate inverter circuitry 2 is controlled by a third clock signal nfclk and a fourth clock signal flck. The clock generating circuitry holds the third and fourth clock signals at fixed values which tristate the tristate inverter circuitry 2 when in scan mode. This moves scan control logic out of the function path comprising the tristate inverter circuitry into the clock control circuitry.
    Type: Application
    Filed: September 11, 2008
    Publication date: March 11, 2010
    Applicant: ARM Limited
    Inventors: Stephen Andrew Kvinta, Marlin Wayne Frederick, Chih-Wei Huang
  • Patent number: 7667489
    Abstract: A voltage regulator and method of voltage regulation for a power-on reset condition are described. Voltage regulation control signals responsive to the power-on reset condition are obtained. The control signals are generated with a first voltage to be associated with a second voltage to provide a first power-on-reset signal and a second power-on-reset signal which are opposite in state to one another. A portion of driver logic is tri-stated responsive to the control signals, and the second power-on-reset signal to at least impede supply to supply current leakage. Voltage is pulled up on a first output port and a second output port of the driver logic responsive to the first power-on-reset signal. A portion of a semiconductor substrate is electrically coupled to a higher one of a first voltage and a second voltage responsive to the pulling up to at least further impede the supply to supply current leakage.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: February 23, 2010
    Assignee: Xilinx, Inc.
    Inventor: Narasimhan Vasudevan
  • Patent number: 7639057
    Abstract: A clock gater includes a first logic circuit that receives an enable signal and that includes first and second subcircuits. The clock gater also includes a latch that shares first and second nodes with the first logic circuit and that includes third and fourth subcircuits. The first logic circuit and the latch receive a clock signal that varies between first and second clock states. The first and third subcircuits pull the first and second nodes, respectively, to a common precharge voltage based on the first clock state in order to pass the clock signal. The second and fourth subcircuits pull the first and second nodes, respectively, to complementary voltages based on the second clock state to pass the clock signal. The first node passes the clock signal or gates the clock signal based on the enable signal.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: December 29, 2009
    Assignee: Marvell International Ltd.
    Inventor: Jason T. Su
  • Patent number: 7633314
    Abstract: System and method for reducing power-on transient current magnitude on distributed header switches. A preferred embodiment comprises a distributed header switch coupling a circuit to a power supply, the distributed header switch comprising a linear sequence of combination switches, each combination switches containing a pre-charge switch and a header switch. A first-pass involves sequentially turning on each of the pre-charge switches, which enables a voltage level at the distributed header switch to approach that of a final voltage level and a second-pass involves sequentially turning on each of the header switches. Since the voltage level at the distributed header switches is close to the final voltage level, a resulting transient current is small in magnitude.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: December 15, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Hugh Mair, Rolf Lagerquist
  • Patent number: 7627070
    Abstract: A device is for detecting a relative positioning of two clock signals including a fast clock signal and a slow clock signal. The fast clock frequency may be n times greater than a slow clock frequency, and n includes an integer greater than 1. The device includes a phase logic signal generator for generating a phase logic signal from the two clock signals by assigning a predetermined logic value to the phase logic signal when a rising edge of the fast clock signal matches a predetermined location of the slow clock signal.
    Type: Grant
    Filed: September 8, 2005
    Date of Patent: December 1, 2009
    Assignee: STMicroelectronics SA
    Inventors: Xavier Cauchy, Eric Salvaire, Cédric Force
  • Patent number: 7626420
    Abstract: An apparatus, system, and method are described for synchronously resetting logic circuits. A synchronous reset signal is coupled to at least one asynchronous reset input for synchronously resetting sequential logic. In one embodiment, reset logic generates a signal coupled to the at least one asynchronous reset input of the sequential logic to synchronously reset the sequential logic.
    Type: Grant
    Filed: September 16, 2005
    Date of Patent: December 1, 2009
    Assignee: NVIDIA Corporation
    Inventor: Elik E. Cohen
  • Patent number: 7617409
    Abstract: A data processing system is provided having a clock signal comparator comprising a reference input port for receiving a reference clock signal and at least a further input port for receiving respective further clock signal. Checking logic is provided within the clock signal comparator to check for a correspondence between the clock edge of the reference clock signal and a corresponding clock edge of the further clock signal within a predetermined time window. The checking logic is operable to check for the correspondence during operation of the data processing system. The clock-signal comparator can be provided on an integrated circuit or as part of the data processing apparatus having at least two different timing domains such as timing domains associated with two different instances of the same clock.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: November 10, 2009
    Assignee: ARM Limited
    Inventors: David Michael Gilday, Daryl Wayne Bradley, Edmond John Simon Ashfield
  • Patent number: 7613853
    Abstract: An improved output buffer having single ended as well as differential signaling capabilities, providing symmetrical outputs for differential output configurations for both synchronous and asynchronous applications, comprising: a pair of flip-flops receiving complementary input signals, a pair of transmitters each having its input connected to the output of one of the flip-flops and providing its output to an output pin, a sense block that senses the transition on complementary input signals and generates a pulse at each transition, and a multiplexer having its output connected to the clock input of said pair of flip flop and one input connected to the output of the sense block for asynchronous mode operation, the second input connected to a clock signal for synchronous mode operation and a select input that enables either asynchronous mode or synchronous mode operation.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: November 3, 2009
    Assignee: STMicroelectronics Pvt. Ltd.
    Inventors: Rajat Chauhan, Rajesh Kaushik
  • Publication number: 20090256593
    Abstract: A system and method for efficient improvement of timing analysis for faster processor designs with negligible impact on die-area. Rather than provide a single clock to flip-flop circuits on a semiconductor chip, split clocks are used. A flip-flop receives a master clock signal for a master latch and receives a separate slave clock signal for a slave latch. Master and slave clock gater circuits are coupled to a global clock distribution system and the local flip-flops. The master clock gater circuit receives a delay control signal used to select a delay, wherein the selected delay determines an additional amount of time the master clock signal transitions after the slave clock signal transitions. The use of the delayed master clock on the semiconductor chip may allow a timing path to have more computation time without increasing the clock cycle time. Further, the delay may be chosen to fix timing paths in post-silicon.
    Type: Application
    Filed: April 9, 2008
    Publication date: October 15, 2009
    Inventor: Samuel D. Naffziger
  • Patent number: 7589565
    Abstract: An improved circuit for reducing a capacitance load on a processor. The circuit includes a global clock circuit capable of producing a primary timing signal. The circuit further includes a local clock buffer circuit having a plurality of outputs. The local clock buffer circuit is connected to the global clock circuit. The local clock buffer circuit is capable of producing a secondary timing signal based on the primary timing signal. The circuit also includes a latch connected to the local clock buffer circuit. The latch is capable of producing a select signal that controls which outputs of the plurality of outputs are active. Only a third signal, based on the secondary timing signal, controls an operation of the latch.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: September 15, 2009
    Assignee: International Business Machines Corporation
    Inventors: Leon J. Sigal, James D. Warnock, Dieter F. Wendel
  • Patent number: 7583103
    Abstract: Configurable time-borrowing flip-flops are provided for circuits such as programmable logic devices. The flip-flops may be based on a configurable delay circuit and two latches or may be based on a configurable pulse generation circuit and a single latch. In designs based on two latches, a first and a second latch are arranged in series. A clock signal is delayed using a configurable delay circuit. Programmable memory elements that have been loaded with configuration data may be used to adjust how much delay is produced by the configurable delay circuit. The delayed version of the clock signal is provided to a clock input associated with the first latch. The second latch has a clock input that receives the clock signal without delay. In designs based on a single latch, a configurable pulse generation circuit receives a clock signal for the flip-flop and generates a corresponding clock pulse for the latch.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: September 1, 2009
    Assignee: Altera Corporation
    Inventors: David Lewis, David Cashman
  • Patent number: 7567096
    Abstract: In particular illustrative embodiments, circuit devices and methods of controlling a voltage swing are disclosed. The method includes receiving a signal at an input of a digital circuit device including a capacitive node. The method also includes selectively activating a voltage level adjustment element to regulate an electrical discharge path from the capacitive node to an electrical ground to prevent complete discharge of the capacitive node. In a particular illustrative embodiment, the received signal may be a clock signal.
    Type: Grant
    Filed: August 23, 2007
    Date of Patent: July 28, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Baker Mohammad, Martin Saint-Laurent, Paul Bassett
  • Patent number: 7518408
    Abstract: A synchronization system to synchronize modules (TX, RX) in an integrated circuit, such as a VLSI integrated circuit, in which the modules receive respective first and second clock signals (TX_CLK, RX_CLK) having a same frequency but being shifted by a constant and unknown phase difference. The system includes a first latch means for latching and delivering data in synchronism with the first clock signal and second latch means for latching data issued from the first latch means and delivering data in synchronism with the second clock signal, first and second latch means being controlled by first and second control signals (strobe_W, strobe_R) elaborated respectively from said first and second clock signals and one of said first and second control signal being shifted by an amount corresponding at least to the set-up time of at least one of said first and second latch means.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: April 14, 2009
    Assignee: STMicroelectronics SA
    Inventors: Riccardo Locatelli, Marcello Coppola, Daniele Mangano, Luca Fanucci, Franscesco Vitullo, Dario Zandri, Nicola L'Insalata
  • Patent number: 7504864
    Abstract: A method for protecting a state machine having an operation modeled by a set of states linked to each other by transitions, the state machine evaluating output signals upon each transition during an evaluation phase according to input signals comprising signals evaluated during a previous transition, the method comprising steps of determining a minimum duration of each evaluation phase according to a minimum duration to evaluate the output signals according to the input signals, and of adjusting the duration of each evaluation phase.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: March 17, 2009
    Assignee: STMicroelectronics S.A.
    Inventors: Laurent Murillo, François Tailliet
  • Patent number: 7501850
    Abstract: A scannable limited switch dynamic logic (LSDL) circuit including a data input and a data output, a combinational logic circuit in communication with the data input, a pre-charge circuit in communication with the combinational logic circuit, a footer circuit in communication with the combinational logic, a keeper circuit in communication with the combinational logic circuit and the pre-charge circuit, a scan input connected to the data input, a scan input circuit in communication with the scan input, the combinational logic circuit, the pre-charge circuit, and the keeper circuit, a modified inverter circuit in communication with the combinational logic circuit, the pre-charge circuit, the keeper circuit, and the scan input circuit, a parallel gate circuit in communication with the modified inverter circuit, a series gate circuit in communication with the modified inverter circuit and the parallel gate circuit, a feedback inverter connected between an internal node and a feedback node, and an output buffer con
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: March 10, 2009
    Assignee: International Business Machines Corporation
    Inventors: Anthony Correale, Jr., Thomas A. Dick, Sven E. Meier, Robert K. Montoye
  • Patent number: 7480846
    Abstract: The invention relates to the domain of turbo decoders. Such a decoder comprises a first decoder (14) and a second decoder (16), each decoder being able to calculate extrinsic output data from extrinsic input data coming from the other decoder. The decoding circuit according to the invention comprises a single memory (31) for storing the extrinsic data. When a decoder calculates an extrinsic output data from an extrinsic input data coming from the other decoder and stored in the single memory at a certain address, this extrinsic output data is then written at this same address.
    Type: Grant
    Filed: May 7, 2003
    Date of Patent: January 20, 2009
    Assignee: ST Wireless SA
    Inventors: Sébastien Charpentier, Patrick Valdenaire
  • Patent number: 7479806
    Abstract: The semiconductor integrated circuit device is a semiconductor integrated circuit device having a pulse generator and a latch circuit. The pulse generator has a first charge/discharge path and a second charge/discharge path and a charge unit for pre-charging first nodes. The first charge/discharge path and the second charge/discharge path include: two first switching units, connected to the first nodes, and configured to control, according to an input signal, conduction and non-conduction of the first charge/discharge path and the second charge/discharge path; and a second switching unit, disposed between a second node and a reference voltage node, and configured to be turned on in a period prior to capturing the input signal to allow an electric charge accumulated at the second node to be discharged to the reference voltage node, and at the same time, configured to be turned on in a period of capturing the input signal to allow the first node to discharge.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: January 20, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Chen Kong Teh, Mototsugu Hamada
  • Patent number: 7454589
    Abstract: There are provided a buffer circuit buffers data between a synchronous circuit and an asynchronous circuit, and a control method therefor. There are also provided an interface circuit that controls data transfer between a synchronous memory circuit and the asynchronous circuit, and a control method therefor, which are used in the buffer circuit and the control method therefor. A data buffer circuit that is interposed between an image processing system and a main system includes a one-port RAM, a control signal generating section, an subsequent cycle address generating section, and a first selector. The first selector selectively outputs the present cycle address to an address of the one-port RAM when an access to the one-port RAM is a write access, and selectively outputs the subsequent cycle address to the address of the one-port RAM when the access to the one-port RAM is a read access.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: November 18, 2008
    Assignee: Fujitsu Limited
    Inventors: Kazuya Taniguchi, Toshiyuki Nishii, Hiromichi Mizuno, Tsutomu Terazawa
  • Patent number: 7429879
    Abstract: A semi-conductor component with a receiver, in particular a clock receiver circuit device, as well as a receiver, in particular a clock receiver circuit device is disclosed. The clock receiver circuit device includes a first input adapted to be connected with a first connection of a semi-conductor component, and second input adapted to be connected with a second connection of the semi-conductor component, wherein the receiver circuit device includes several, in particular more than three transfer gates.
    Type: Grant
    Filed: September 10, 2004
    Date of Patent: September 30, 2008
    Assignee: Infineon Technologies AG
    Inventor: Alessandro Minzoni
  • Patent number: 7363560
    Abstract: According to one aspect of the invention, a circuit for determining the location of a defect in an integrated circuit is described. The circuit comprises a conductor extending from a first node to a second node and a test signal driver coupled to the first node of the conductor. The test signal driver receives a test signal using a first clock signal, while a plurality of detector circuits coupled to the conductor between the first node and the second node to detect an output at the plurality of nodes using a second clock signal. According to other embodiments, circuits for determining the location of a defect in a programmable logic device are disclosed. Finally, various methods for determining the location of a defect in an integrated circuit are described.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: April 22, 2008
    Assignee: Xilinx, Inc.
    Inventors: David Mark, Yuezhen Fan
  • Patent number: 7352212
    Abstract: We propose an opposite-phase scheme for peak current reduction. The basic idea is to divide the clock buffers at each level of the clock tree into two sets: one half of the clock buffers operate at the same phase as the clock source, and the other half of the clock buffers operate at the opposite phase to the clock source. Consequently, our approach can effectively reduce the peak current of the clock tree. The method enables the opposite-phase scheme to combine with the electronic design automation (EDA) tools that are commonly used in modern industries.
    Type: Grant
    Filed: November 23, 2005
    Date of Patent: April 1, 2008
    Assignees: Industrial Technology Research Institute, Chung Yuan Christian University
    Inventors: Yow-Tyng Nieh, Sheng-Yu Hsu, Shih-Hsu Huang, Yeong-Jar Chang
  • Patent number: 7346861
    Abstract: Programmable logic circuitry includes level-sensitive latches as at least some of the data storage elements. At least some of the latches are enabled by one phase of a clock signal, and at least some others of the latches are enabled by the other phase of the clock signal. Accordingly, these latches collectively have two-phase operation. These two-phase latches may replace at least some single-phase, edge-triggered flip-flops in a user's logic design, and may thereby increase the speed at which the user's logic can be operated. Methods for converting a single-phase, edge-triggered flip-flop design to a logically equivalent design using at least some two-phase latches are disclosed.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: March 18, 2008
    Assignee: Altera Corporation
    Inventor: Andy L Lee
  • Patent number: 7339403
    Abstract: Clock error detections circuits can detect clock duty cycle error and/or quadrature phase error. During an evaluation phase, capacitors are charged. During an evaluation phase, the capacitors are unequally discharged based on the error. A positive feedback mechanism latches the result.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: March 4, 2008
    Assignee: Intel Corporation
    Inventors: Suwei Chen, Derek M. Conrow, Aaron K. Martin
  • Patent number: 7323909
    Abstract: A method extends a clock-gating technique to provide a sleep signal for controlling switch circuits that reduce active leakage power. Using this extension of the clock-gating technique, fine-grained power-gating is achieved. The method automatically identifies, at an RTL or a gate level, the logic circuits that can be power-gated. The method of the present invention derives a sleep signal for fine-grained power-gating that may be applicable to both time-critical and non-time-critical designs.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: January 29, 2008
    Assignee: Sequence Design, Inc.
    Inventor: Mahesh Mamidipaka
  • Patent number: 7301373
    Abstract: A flip-flop circuit includes a differential stage coupled to a latch stage. The differential stage comprises cross-coupled dynamic logic and only provides a single output to the latch stage. During an evaluation phase, the state of a data input signal is sensed. Depending upon the state of the data input signal, either an output side or reference side of the differential stage is discharged. Also, during the evaluation phase, the latch stage write port is enabled while feedback is disabled, and the flip flop thereby samples and stores an output signal from the output side of the differential stage. Upon initiation of the next precharge phase, the latch stage write port is disabled and feedback is enabled, thereby retaining its present state. Only a single side of the differential stage is used to drive the latch stage and the differential stage may be implemented in an asymmetric fashion.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: November 27, 2007
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Daniel William Bailey, Hariharan Kalyanaraman
  • Patent number: 7298171
    Abstract: A layout area efficient, high speed, dynamic multi-input exclusive OR (XOR) and exclusive NOR (XNOR) logic gate circuit design of especial utility with respect to integrated circuit devices. The logic gate design disclosed herein utilizes fewer transistors than traditional static designs and, therefore, requires a smaller amount of integrated circuit layout area while nevertheless affording higher speed operating performance than that exhibited in existing conventional circuits.
    Type: Grant
    Filed: July 8, 2005
    Date of Patent: November 20, 2007
    Assignees: United Memories, Inc., Sony Corporation
    Inventor: Michael C. Parris
  • Patent number: 7293190
    Abstract: A clock filter for use in filtering an external clock signal to create an internal clock signal for use by an electronic device is provided. The clock filter receives the external clock signal and sets the internal clock signal high when the external clock signal is above a first threshold and sets the internal clock signal low when the external clock signal is below a second threshold. The clock filter holds the internal clock signal constant for a period of time after the clock transitions.
    Type: Grant
    Filed: November 24, 2003
    Date of Patent: November 6, 2007
    Assignee: Infineon Technologies AG
    Inventor: Thomas Vogelsang
  • Patent number: 7285985
    Abstract: A logic circuit comprises: an event generator for detecting a variation in data output from a signal source to generate an event which indicates the variation of the data; a plurality of propagation elements for propagating the event in a chained fashion; and a plurality of evaluation elements for evaluating data received at a first stage from the signal source to propagate a result of the evaluation in a chained fashion. When receiving the event, each of the plurality of evaluation elements evaluates the data input to the evaluation element.
    Type: Grant
    Filed: August 3, 2005
    Date of Patent: October 23, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yukihiro Sasagawa, Atsushi Takahata
  • Patent number: 7282957
    Abstract: In a dynamic flip-flop circuit with a data selection function, for example, when data having an H value is selected using a selection signal, a first node N1 is L, a second node N2 of a second dynamic circuit is H, so that an output signal has an H level. In this case, when none of a plurality of pieces of data is selected using a selection signal, the first node N1 is H, so that the electric charge of the second node N2 is discharged and the output signal erroneously has an L level. However, in this case, an output node N3 is H and a fourth node N4 is L, so that an n-type transistor of the second dynamic circuit is turned OFF, thereby preventing the second node N2 from being discharged. Therefore, a normal operation is performed while securing a satisfactorily high-speed operation even when none of the pieces of data is selected.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: October 16, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Masaya Sumita
  • Patent number: 7282960
    Abstract: A dynamic logical circuit having a pre-charge element separately controlled by a voltage-asymmetric clock controlled provides increased noise immunity in dynamic digital circuits. By clocking the pre-charge element with a signal having a reduced swing in the voltage direction that turns off the pre-charge element, the pre-charge element provides a small current that prevents the dynamic summing node of a gate from erroneously evaluating due to noise, and eliminates the need for a keeper device. Providing the reduced-swing asymmetric clock as a separate signal prevents performance degradation in the rest of the circuit. Specifically, the foot devices in the dynamic portion of the circuit are controlled with the full swing clock so that evaluation is not compromised by noise or slowed. Foot and pull-up devices in any static portion of the circuit are also controlled with the full-swing clock so that switching speed and leakage immunity are not affected.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: October 16, 2007
    Assignee: International Business Machines Corporation
    Inventors: Wendy Ann Belluomini, Robert Kevin Montoye, Aniket Mukul Saha
  • Patent number: 7280628
    Abstract: Method and apparatus for data recapture from a source synchronous interface. A data signal is obtained via the source synchronous interface. A timing signal is obtained via the source synchronous interface, where the data signal and the timing signal are provided in association with one another. The timing signal is frequency divided by frequency divider to provide an enable signal. Data of the data signal is captured responsive to the timing signal and the enable signal, where the data captured is in a time domain of the timing signal. A data valid signal is generated from the enable signal and an internal clock signal, where the data valid signal is internally timed without having to determine a system level delay. The data is recaptured responsive to the internal clock signal and the data valid signal, where the recaptured data is in a time domain of the internal clock signal.
    Type: Grant
    Filed: October 14, 2003
    Date of Patent: October 9, 2007
    Assignee: Xilinx, Inc.
    Inventors: Chandrasekaran N. Gupta, Maria George, Lakshmi Gopalakrishnan
  • Patent number: 7265589
    Abstract: A dynamic logic gate has a dynamic node pre-charged in response to a pre-charge phase of a clock signal and a logic tree with a plurality of logic inputs for evaluating the dynamic node during an evaluate phase of the clock signal in response to a Boolean combination of the logic inputs. The logic tree has a stacked configuration with at least one multi-gate FEAT device for coupling an intermediate node of the logic tree to the dynamic node in response to a first logic input of the plurality of logic inputs or in response to the pre-charge phase of the clock signal. The multi-gate FEAT device has one gate coupled to the first logic input and a second gate coupled to a complement of the clock signal used to pre-charge the dynamic node.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: September 4, 2007
    Assignee: International Business Machines Corporation
    Inventors: Ching-Te Chuang, Keunwoo Kim, Jente Benedict Kuang, Kevin John Nowka
  • Patent number: 7259594
    Abstract: A chain of processing element (10a, 10, 10b) with a logic circuit (14) and a storage element (12) is provided. The storage elements (12) of all except a final processing element (10b) in the chain have one or more outputs coupled to the logic (14) of a next processing element (10a, 10, 10b) in the chain. A timing circuit (16) controls respective loading time points at which the storage elements (12) load data from the logic circuits (14) in respective ones of the processing elements (10a, 10, 10b). The data is loaded progressively later in processing elements (10a, 10, 10b) that successively precede one another in the chain. The time interval between successive loading time points of the final processing element (10b) includes loading time points of loading all processing elements (10a, 10) other than the final processing element (10).
    Type: Grant
    Filed: August 30, 2004
    Date of Patent: August 21, 2007
    Assignee: NXP B.V.
    Inventors: Adrianus Marinus Gerardus Peeters, Cornelis Hermanus Van Berkel, Mark Nadim Olivier De Clercq
  • Patent number: 7245157
    Abstract: A primarily domino logic block uses static buffers instead of clocked domino buffers to correct a phase skipping problem, while realizing the same logic function with less integrated circuit area, power consumption, and cost. The use of static buffers simplifies the clock network and clock tree synthesis. A domino logic circuit including at least one logic gate including a fast input and a slow input, and a static buffer inserted in series with the fast input of the logic gate. The falling time of the static buffer is set to be greater than a defined minimum falling time and less than a defined maximum falling time.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: July 17, 2007
    Assignee: STMicroelectronics, Inc.
    Inventor: Bernard Bourgin
  • Patent number: 7230985
    Abstract: A look-ahead decision feedback equalizing receiver includes an equalizing block for amplifying a high-frequency component of an external data signal fed thereto in response to a first and a second input signal, to provide a first and a second equalized external data signal; a clock synthesizer for outputting sampling clocks, a timing thereof being adjusted by receiving an external clock synchronized with the external data signal; an over-sampler for over-sampling the first and the second equalized external data signal in synchronization with the sampling clocks. A MUX block for multiplexing the outputs of the over-sampler in response to outputs of the MUX block, to thereby attain decision results; and a phase detector for deciding the timing of the sampling clock by analyzing the decision results.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: June 12, 2007
    Assignee: Postech Foundation
    Inventors: Hong-June Park, Young-Soo Sohn
  • Patent number: 7218160
    Abstract: A semiconductor integrated circuit according to the present invention comprises a latch circuit, a retaining circuit, and a feedback circuit, wherein the latch circuit inputs therein an input data signal, a clock signal and a feedback signal and outputs an output data signal, the retaining circuit retains the output data signal, and the feedback circuit inputs therein the input data signal and the output data signal to thereby generate the feedback signal based on logic combinations of the input data signal and the output data signal, and an internal operation of the latch circuit is turned on/off by means of the feedback signal.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: May 15, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tooru Wada, Masaya Sumita
  • Patent number: 7212039
    Abstract: A dynamic logic register including a complementary pair of evaluation devices, delayed inversion logic, a dynamic evaluator, latching logic, and a keeper circuit coupled to the output. The evaluation devices are responsive to a clock signal and provide a pre-charged node and an evaluation node. The delayed inversion logic outputs a complete signal that is a delayed and inverted version of the clock signal. The dynamic evaluator, coupled between the pre-charged and evaluation nodes, evaluates a logic function based on a data signal during an evaluation period between operative edges of the clock and complete signals. The latching logic enables the state of an output node to be determined by the state of the pre-charged node during the evaluation period and otherwise clamps the pre-charged node to prevent perturbations of the data signal from propagating to the output node.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: May 1, 2007
    Assignee: Via Technologies, Inc.
    Inventors: Imran Qureshi, James R. Lundberg
  • Patent number: 7213184
    Abstract: Testing of modules (such as Intellectual property (IP) cores) in integrated circuits (such as system on a chip units (SOCs)) in situations when different modules operate with different characteristics of a control signal. In an embodiment, another module (“subsystem module”) may be implemented to be tested with any of a multiple characteristics of a control signal, and a register which is programmable to generate a derived control signal of a desired characteristic from an original control signal, is provided. The derived control signal is provided to test the subsystem module. According to an aspect of the invention the desired characteristic may be determined, for example, to test a path between the two modules at the same speed as at which the path would be operated in a functional mode.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: May 1, 2007
    Assignee: Texas Instruments Incorporated
    Inventors: Nikila Krishnamoorthy, Anindya Saha, Rubin Ajit Parekhji
  • Patent number: 7202704
    Abstract: A method and apparatus for ensuring proper operation of a dynamic circuit is provided. A dynamic circuit instance has a plurality of outputs connected to a respective one of a plurality of leakage detector circuits. An output of each leakage detector circuit is connected with a respective one of a plurality of keeper circuits that reside at the dynamic circuit. Each of the plurality of keeper circuits has a unique size ratio with respect to a logic element size of the dynamic circuit.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: April 10, 2007
    Assignee: International Business Machines Corporation
    Inventors: Sam Gat-Shang Chu, Peter Juergen Klim, Michael Ju Hyeok Lee, Jose Angel Paredes