Master-slave Bistable Latch Patents (Class 327/202)
  • Patent number: 7508902
    Abstract: A shift register including a plurality of stage circuits is provided. Each of the stage circuits has a shift circuit for receiving an input signal and providing an output signal. The output signal is obtained through the logic calculation and delaying of the input signal. Each of the stage circuits, except the first one, further includes a logic circuit used to produce at least one control signal according to the internal signals of the containing stage circuit, so as to replace at least one of the required clock signals during the operation of the corresponding shift circuit.
    Type: Grant
    Filed: July 17, 2006
    Date of Patent: March 24, 2009
    Assignee: Chunghwa Picture Tubes Ltd.
    Inventors: Cheng-Hung Tsai, Chun-Yao Huang, Yi-Feng Liao
  • Publication number: 20090066387
    Abstract: A latch circuit (1) comprising a first input device (10a) in a first branch (4a) and a second input device (10b) in a second branch (4b). The latch circuit comprises a first estimator unit (40a) adapted to generate a first estimate of a current generated by the first input device (10a) and a second estimator unit (40b) adapted to generate a second estimate of a current generated by the second input device (10b). The latch circuit further comprises a control-voltage unit (50) operatively connected to the first and the second estimator unit (40a, 40b). The control-voltage unit is adapted to generate a control voltage based on a sum of the first estimate and the second estimate. Further, the latch circuit (1) comprises a first and a second voltage-controlled current unit (30a, 30b) adapted to generate currents at least based on the control voltage. The first voltage-controlled current unit (30a) is operatively connected to the first branch (4a).
    Type: Application
    Filed: January 18, 2007
    Publication date: March 12, 2009
    Applicant: SICON SEMICONDUCTOR AB
    Inventor: Rolf Sundblad
  • Publication number: 20090066385
    Abstract: A latch of an integrated circuit is able to retain data at the latch when the integrated circuit is in a low-power mode. The latch retains data at a retention stage in response to assertion of an isolation signal. In response to a reference voltage supplied to the latch being restored to a normal operating voltage, indicating that the integrated circuit has transitioned from the low-power mode to a normal mode, a data restoration circuit provides the retained data at the output of the latch prior to negation of the isolation signal. This reduces the likelihood that a delay in negation of the isolation signal will result in the latch output providing incorrect data, thereby reducing the likelihood of the latch output causing errors in downstream elements of the integrated circuit.
    Type: Application
    Filed: September 12, 2007
    Publication date: March 12, 2009
    Applicant: FREESCALE SEMICONDUCTOR, INC.
    Inventor: Andrew P. Hoover
  • Publication number: 20090066386
    Abstract: There is provided a MTCMOS flip-flop configured to operate at high speed and to reduce leakage current while realizing a retention function in a sleep mode. The MTCMOS flip-flop may include a signal generator adapted to output an internal clock signal or a sleep mode control signal based on changes in a retention signal and an external clock signal, a master latch adapted to latch an input signal and to output a master latch output signal based on the internal clock signal, and a slave latch connected to an actual ground and adapted to latch the master latch signal, to output a slave latch output signal under control of the internal clock signal, and to maintain the latched signal under control of the sleep mode control signal in the sleep mode.
    Type: Application
    Filed: August 20, 2008
    Publication date: March 12, 2009
    Applicant: DONGBU HITEK CO., LTD.
    Inventor: Jae Jun LEE
  • Patent number: 7501871
    Abstract: A latch circuit comprising, a differential input with a non-inverting input (D+) and an inverting input (D?). The latch further comprises a differential output with a non-inverting output (Q+) and an inverting output (Q?). One of the outputs (Q?) is coupled to one of the inputs input (D+) having an opposite polarity. The latch further comprises a control input for receiving a control signal (VcM) for determining a threshold for an input signal (In) such that if the input signal is at larger than the threshold the non-inverting output is in a HIGH logic state and in a LOW state if the input signal is smaller than the threshold.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: March 10, 2009
    Assignee: NXP B.V.
    Inventors: Mihai Adrian Tiberiu Sanduleanu, Eduard Ferdinand Stikvoort, Idrissa Cissé
  • Publication number: 20090058484
    Abstract: In a method and apparatus for data retention, a first latch latches a data input and a second latch that is coupled to the first latch retains the data input while the first latch is inoperative in a standby power mode. The second latch includes a second latch inverter having an inverter input and an inverter output. A switching circuit, which may be implemented as a tristate inverter, is coupled to the inverter output, the inverter input, and a retention signal. The switching circuit is operable in the standby power mode to assert a logic state at the inverter input responsive to the retention signal. The logic state is in accordance with the data input retained in the standby power mode. A standby power source is operable to provide power in the standby power mode to the second latch inverter, the switching circuit and the retention input.
    Type: Application
    Filed: August 27, 2007
    Publication date: March 5, 2009
    Inventors: Bindu Prabhakar Rao, Sumanth Katte Gururajarao, Dharin N. Shah
  • Patent number: 7495492
    Abstract: The invention comprises a dynamic voltage state-saving latch electrical circuit comprising a charge device adapted as a storage element, an integrated recovery mechanism, a supply voltage rail connected to the charge device, a hold signal allocated to the integrated recovery mechanism, a data signal input allocated to said charge device, a data signal output distributed from the charge device, and a clock signal allotted to the charge device, wherein said integrated recovery mechanism maintains a state of the charge device independent of the charge device.
    Type: Grant
    Filed: September 12, 2006
    Date of Patent: February 24, 2009
    Assignee: International Business Machines Corporation
    Inventors: Pascal A. Nsame, Anthony J. Perri, Lansing U. Pickup, Sebastian T. Ventrone, Matthew R. Walland
  • Patent number: 7492201
    Abstract: A clocked level-sensitive scan design may have flip-flops designed to have data, scan-in, and output ports and to utilize two clock signals. Such a clocked level-sensitive scan flip-flop may be built utilizing two latches.
    Type: Grant
    Filed: August 27, 2007
    Date of Patent: February 17, 2009
    Assignee: Marvell International Ltd.
    Inventor: Randy J. Aksamit
  • Publication number: 20090039936
    Abstract: Example embodiments relate to an electronic circuit, for example, a flip-flop circuit, a pipeline circuit including the flip-flop circuit and a method for operating the flip-flop circuit. A flip-flop circuit may include a precharge transistor configured to precharge an internal node to a first power supply voltage in response to a clock signal, a first pull-down unit configured to pull down a voltage of the internal node to a second power supply voltage, a pull-up transistor configured to pull up a voltage of an output node to the first power supply voltage in response to the voltage of the internal node, and a second pull-down unit configured to pull down the voltage of the output node to the second power supply voltage. The pipeline circuit may include a pulse generating circuit, a first flip-flop group, a combination logic circuit, and a second flip-flop group.
    Type: Application
    Filed: August 11, 2008
    Publication date: February 12, 2009
    Inventor: Min-su Kim
  • Patent number: 7489174
    Abstract: A dynamic flip-flop circuit which outputs an output signal on which a digital data signal is reflected based on a clock, includes: a first control stage configured to output a signal having a level inverted from that of the digital data signal within a period within which the clock has a second level; a second control stage configured to output a signal of a first level within the period within which the clock has the second level and a signal of a level within another period within which the clock has the first level; a third control stage configured to output an output signal of the first level within a period within which the signal outputted from the second control stage has the second level; and a phase adjustment circuit configured to adjust the phase to produce a second clock and supply the second clock to the third control stage.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: February 10, 2009
    Assignee: Sony Corporation
    Inventor: Atsushi Yoshizawa
  • Patent number: 7486123
    Abstract: A method and latch circuits are provided for implementing enhanced noise immunity performance. Each latch circuit includes an L1 latch and an L2 latch coupled to the L1 latch. Data is first latched in the L1 latch during a first half clock cycle and then latched in the L2 latch during a second half clock cycle. A path opposite a latched data state is gated off in both the L1 latch and the L2 latch, where a path to a voltage supply rail is gated off with a latched low data state and a path to ground is gated off with a latched high data state.
    Type: Grant
    Filed: January 10, 2008
    Date of Patent: February 3, 2009
    Assignee: International Business Machines Corporation
    Inventors: David Jia Chen, Eugene James Nosowicz
  • Patent number: 7482851
    Abstract: An edge triggered system is provided having a data and scan input includes a latch device having a clock input and an AND gate, coupled to the latch device, structured and arranged to receive a first clock signal and an inverted clock signal to generate a clock to the clock input. A process for operating an edge triggered system having a data and scan input includes forwarding a first clock signal to an input of an AND gate. The method includes inverting a second clock signal forwarded to another input of the AND gate and generating a clock input for a latch device from the AND gate.
    Type: Grant
    Filed: June 18, 2007
    Date of Patent: January 27, 2009
    Assignee: International Business Machines Corporation
    Inventors: David E. Lackey, Steven F. Oakland, Peter Verwegen
  • 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
  • Publication number: 20090002044
    Abstract: A master-slave type flip-flop circuit consisting of a master latch and a slave latch, wherein the master latch comprises: a first clocked inverter to which data are input and a first latch circuit configuring a closed circuit with a first inverter and a second clocked inverter so that an output of the first clocked inverter is input to the first inverter and; the slave latch comprises: a transmission gate to which an output from the first latch circuit is input and a second latch circuit configuring a closed circuit with a second inverter and a third clocked inverter so that an output of the transmission gate is input to the second inverter, respective components configuring the master latch and the slave latch are configured with Sea Of Gate (hereinafter to be referred to as SOG) configuring a gate array, a basic cell of the SOG consists of triplely arrayed N-type transistors and corresponding triplely arrayed P-type transistors, the triplely arrayed N-type transistors consist of double-arrayed normally size
    Type: Application
    Filed: June 20, 2008
    Publication date: January 1, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Shinichiro Kobayashi
  • Publication number: 20080315912
    Abstract: According to an aspect of an embodiment, a logic circuit includes a first master latch included in one of the master-slave flip-flop circuits, the first master latch having a first scan data input for receiving scan data, the first master latch latching the scan data and outputting latched scan data, a second master latch included in another of the master-slave flip-flop circuits, the second master latch having a second scan data input operatively connected to receive an output of the first master latch, the second master latch latching the scan data inputted into the second scan data input and outputting latched scan data and a slave latch included in one of the master-slave flip-flop circuits, the slave latch having a scan data input operatively connected to receive an output of the second master latch.
    Type: Application
    Filed: June 10, 2008
    Publication date: December 25, 2008
    Applicant: FUJITSU LIMITED
    Inventor: Yoshihiko Satsukawa
  • Publication number: 20080315932
    Abstract: A flip-flop includes a functional latch and a retention latch. The functional latch is configured to maintain a logic state of the flip-flop in a power-up mode and the retention latch is configured to maintain the logic state of the flip-flop in a power-down mode. The retention latch is selectively coupled to the functional latch and the retention latch is configured to maintain the logic state in the power-down mode irrespective of a level of an associated clock signal when the power-down mode is entered. A clock pulse that clocks the flip-flop is derived from the associated clock signal.
    Type: Application
    Filed: June 22, 2007
    Publication date: December 25, 2008
    Inventors: Samuel J. Tower, Matthew S. Berzins, Charles A. Cornell
  • Publication number: 20080303573
    Abstract: A latch includes a data input terminal for receiving a data signal; a data output terminal for outputting the data signal; a first control terminal for receiving a control signal to set or reset the data signal derived from the data output terminal; a sleep signal input terminal for receiving a sleep signal to determine a sleep mode; a first logic circuit having input terminals coupled to the data input terminal, the first control terminal and the sleep signal input terminal and an output terminal coupled to the data output terminal; and a second logic circuit having input terminals coupled to the data output terminal, the first control terminal and the sleep signal input terminal and an output terminal coupled to the data input terminal; wherein the first logic circuit or the second logic circuit ignores the first control signal in response to the sleep signal when the latch is operated in the sleep mode.
    Type: Application
    Filed: June 11, 2007
    Publication date: December 11, 2008
    Applicant: FARADAY TECHNOLOGY CORPORATION
    Inventors: Shang-Chih Hsieh, Jeng-Huang Wu
  • Publication number: 20080297219
    Abstract: Equal delay flip-flop systems and complementary input complementary output equal delay flip-flop circuits are disclosed. In one embodiment, an equal delay flip-flop system includes a first delay flip-flop for processing a first input, including a first tri-state input driver for driving the first input, a first master latch for sampling and/or forwarding the first input, a first transmission gate for relaying the first input forwarded by the first master latch, and a first slave latch for storing and/or forwarding the first input. The equal delay flip-flop system further includes a second delay flip-flop for processing a second input, including a second tri-state input driver for driving the second input, a second master latch for sampling and/or forwarding the second input, a second transmission gate for relaying the second input forwarded by the second master latch, and a second slave latch for storing and/or forwarding the second input.
    Type: Application
    Filed: April 23, 2008
    Publication date: December 4, 2008
    Inventors: SUJAN MANOHAR, Pavan Vithal Torvi
  • Patent number: 7453294
    Abstract: A dynamic frequency divider circuit with improved leakage tolerance supports a wide frequency range. During the evaluation phase, (1) the input signals can be prevented from changing states, (2) the leakage can be reduced, or (3) both can be implemented to generate the correct output signals. In a architecture-level approach, two dynamic flip-flops can be coupled together. In a circuit-level approach, the dynamic flip-flop can include (1) two additional clocked PMOS transistor added to the inputs of the dynamic flip-flop, or (2) two additional pull-up PMOS transistors to counteract the subthreshold leakage in the NMOS transistors.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: November 18, 2008
    Assignee: Altera Corporation
    Inventors: Shoujun Wang, Haitao Mei, Bill Bereza
  • Publication number: 20080265962
    Abstract: A circuit has a master latch having an input for receiving an input data signal, and an output. A slave latch has a first input coupled to the output of the master latch, and an output for providing an output data signal. A non-volatile storage element stores a predetermined value. The non-volatile storage element has an output coupled to the first input of the slave latch. The output data signal corresponds to one of either the input data signal or the predetermined value stored by the non-volatile storage element in response to a control signal.
    Type: Application
    Filed: April 30, 2007
    Publication date: October 30, 2008
    Inventors: Jeffrey W. Waldrip, Alexander B. Hoefler
  • Publication number: 20080258789
    Abstract: A flip-flop is disclosed which includes: a clock supply circuit configured to output or fix a clock signal alternating between two predetermined states in accordance with a sleep signal; a first holding circuit configured to fetch or hold an input signal in accordance with a state the clock signal indicates; a second holding circuit configured to fetch or hold a first signal output by the first holding circuit in accordance with a state the clock signal indicates; an input switching circuit configured to supply as the input signal a second signal output by the second holding circuit or to supply an external signal as the input signal in accordance with the hold signal; and a power supply control circuit configured to supply or not to supply power to the first holding circuit and the input switching circuit in accordance with a power supply control signal.
    Type: Application
    Filed: October 23, 2007
    Publication date: October 23, 2008
    Applicant: Sony Corporation
    Inventor: Tetsuo Motomura
  • Patent number: 7440534
    Abstract: A master latch (1) is formed from a static circuit, and a slave latch (2) is formed from a dynamic circuit. The number of circuit elements can be smaller as compared to a slave latch formed from a static circuit so that the size and area of a master-slave flip-flop can be reduced. Since the master latch is formed from a static circuit, data can be held stably during the standby time by setting the master latch in a data holding state.
    Type: Grant
    Filed: August 9, 2005
    Date of Patent: October 21, 2008
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Hiroki Morimura, Satoshi Shigematsu, Yukio Okazaki, Katsuyuki Machida
  • Publication number: 20080253500
    Abstract: A flip-flop is provided. The flip-flop is used in a shift register in a source driver. The flip-flop is used to receive a first clock signal, an input signal and output an output signal. The output signal is fed back to the flip-flop. The flip-flop includes a flop core for receiving the input signal and output the output signal. When the input signal and the output signal are all disabled, the flop core is disabled to function. When the input signal or the output signal is enabled, the flop core is enabled to function to output the output signal.
    Type: Application
    Filed: March 3, 2008
    Publication date: October 16, 2008
    Applicant: Raydium Semiconductor Corporation
    Inventors: Ko-Yang Tso, Hui-Wen Miao, Chin-Chieh Chao
  • Patent number: 7437634
    Abstract: A sequential scan cell includes an input port for functional data and an input for scan test data. The input for scan test data is an input to a master scan flip-flop coupled to a slave scan flip-flop defining a scan test circuit. Such a scan test circuit is coupled to the functional circuit of the sequential scan cell such that the path for a functional signal is not through the scan test circuit, imparting no performance penalty to the functional signal. Scan test data is scanned in and out of the sequential cell by two non-overlapping scan clocks that are active only when system functional clocks are in an off state.
    Type: Grant
    Filed: May 13, 2003
    Date of Patent: October 14, 2008
    Assignee: Intel Corporation
    Inventors: Talal K. Jaber, Anil K. Sabbavarapu
  • Patent number: 7427875
    Abstract: Signal delivery delay margin of a bypass flip-flop circuit is stabilized during high-frequency operation. An input controller for logically operating a bypass signal and a clock produces first and second output signals having different states depending on whether or not the bypass signal is activated. A latch circuit latches input data based on the first and second output signals. A latch controller logically operates the bypass signal and input data to generate a third output signal having a different state depending on whether or not the bypass signal is activated. An output controller is switched in response to the states of the first and second output signals for logically combining an output signal selected from the latch circuit and the third output signal to provide the output signal.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: September 23, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventors: Kyung-Hoon Kim, Tae-Heui Kwon
  • Patent number: 7425855
    Abstract: A method and latch circuits are provided for implementing enhanced noise immunity performance. Each latch circuit includes any L1 latch and an L2 latch coupled to the L1 latch. Data is first latched in the L1 latch during a first half clock cycle and then latched in the L2 latch during a second half clock cycle. A path opposite a latched data state is gated off in both the L1 latch and the L2 latch, where a path to a voltage supply rail is gated off with a latched low data state and a path to ground is gated off with a latched high data state.
    Type: Grant
    Filed: July 14, 2005
    Date of Patent: September 16, 2008
    Assignee: International Business Machines Corporation
    Inventors: David Jia Chen, Eugene James Nosowicz
  • Publication number: 20080218234
    Abstract: A flip-flop circuit having low power consumption includes a sensing circuit, and a clock generating circuit. The flip-flop is leading edge triggered and operates on an internally generated pseudo clock signal. The sensing circuit senses a change in an input signal and an output signal of the flip-flop. The clock generating circuit generates a pseudo clock signal with a sharp rise and fall based upon an external clock signal.
    Type: Application
    Filed: December 27, 2007
    Publication date: September 11, 2008
    Applicant: STMicroelectronics Pvt. Ltd.
    Inventor: Abhishek Jain
  • Publication number: 20080218233
    Abstract: A clock input circuit 13 receives power during standby mode and comprises a NAND circuit NAND0 that controls a clock signal CK using a standby mode signal RET. When the standby mode signal RET is at a low level (in standby mode) clock signals C01 and C02 are kept at a high level and low level respectively regardless of the level of the clock signal CK. Further, power continues to be supplied to an FA section in the clock input circuit 13 and to an FB section in a slave latch circuit 12 whereas the power supply to the other circuits is shut off. As a result, the clock signals C01 and C02 remain at the high level and low level respectively and data is held by a loop formed by an on-state transfer gate circuit TG4 and activated inverter circuits INV5 and INV6 in the slave latch circuit 12.
    Type: Application
    Filed: March 4, 2008
    Publication date: September 11, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Hiroshi Yamamoto, Makoto Nonaka
  • Publication number: 20080211558
    Abstract: A design structure embodied in a machine readable medium includes information for designing, manufacturing and/or testing a programmable phase frequency divider circuit implemented in CMOS technology for space applications. The programmable phase frequency divider consists of three radiation hardened D-type flip flops and combinational logic circuits to provide the feedback controls that allow programmable frequency division ratios from 1 to 8. The radiation hardened D-type flip flop circuits are designed to keep on running properly at GHz frequencies even after a single event upset (SEU) hit. The novel D-type flip flop circuits each have two pairs of complementary inputs and outputs to mitigate SEU'S. The combinational logic circuits are designed to utilize the complementary outputs in such a way that only one of the four dual complementary inputs to any D-type flip flop gets flipped at most after an SEU hit.
    Type: Application
    Filed: March 27, 2008
    Publication date: September 4, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventor: William Yeh-Yung Mo
  • Patent number: 7420403
    Abstract: A high-reliability, multi-threshold complementary metal oxide semiconductor (CMOS) latch circuit is presented that uses both low and high threshold inverters. The multi-threshold latch circuit includes: a low threshold forward clock inverter inverting an input-terminal logic state and applying the inverted logic state to an output-terminal logic state when a clock is in a first logic state; and a high threshold backward clock inverter forming a circular latch structure together with the forward clock inverter, and inverting an input-terminal logic state and applying the inverted logic state to an output logic state when the clock is in a second logic state.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: September 2, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Yil Suk Yang, Jong Dae Kim, Tae Moon Roh, Dae Woo Lee
  • Patent number: 7420402
    Abstract: A latch section includes a latch circuit. The latch circuit includes inverters and latches an input signal from a gating section. Between one of the inverters of the latch circuit and the output terminal OUT is disposed an analog switch whose ON/OFF characteristics are switched according to High/Low of a reset signal. Between the output terminal and an input for receiving a low potential as a power supply of a flip-flop is disposed a switching element whose ON/OFF characteristics are switched according to High/Low of the reset signal.
    Type: Grant
    Filed: January 27, 2005
    Date of Patent: September 2, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hajime Washio, Yuhichiroh Murakami, Michael James Brownlow
  • Publication number: 20080204100
    Abstract: For example, a gain control part and a common node control part are provided in a logic circuit including a data acquisition part that has a differential amplifier configuration and acquires a data input signal when a click signal is an “H” level and a latch part that latches a data output signal from the data acquisition part when the click signal is an “L” level. The gain control part is provided between common nodes of NMOS transistors in the differential amplifier and serves to make the gain of the differential amplifier higher in a high frequency band than in a low frequency band. When the clock signal is an “L” level, the common node control part serves to control an electrical charge so as to eliminate a potential difference between the common nodes. Thus, the transition time of the data output signal is speeded up and the setup margin is increased in the latch part. The above described technique can therefore speed up operations of various logic circuits such as a latch circuit.
    Type: Application
    Filed: December 26, 2007
    Publication date: August 28, 2008
    Inventors: Fumio Yuuki, Hiroki Yamashita, Masayoshi Yagyu, Koji Fukuda
  • Publication number: 20080191769
    Abstract: A CAD device according to the embodiments includes means that determines signal transmission time of each signal transmission circuit in an LSI circuit, means that determines an output inversion rate of a flip-flop circuit included in each signal transmission circuit when the flip-flop circuit is exposed to radiation, means that determines a signal transmission circuit that is a critical path, means that calculates a total soft error rate of the LSI circuit on the basis of the signal transmission time, the output inversion rate, and a clock period, and means that, when a predetermined soft error rate is less than the total soft error rate of the LSI circuit as a result of comparison, reducing the total soft error rate of the LSI circuit to the extent possible without changing signal transmission time of the signal transmission circuit, which is a critical path.
    Type: Application
    Filed: March 24, 2008
    Publication date: August 14, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Taiki Uemura, Yoshiharu Tosaka
  • Patent number: 7411432
    Abstract: An integrated circuit of an embodiment may comprise synchronous logic, combinational logic, and clock circuitry to clock the synchronous logic through various states dependent on the combinational logic. The synchronous logic may comprise a plurality of master-slave registers. The combinational logic is configured to drive data inputs of the synchronous logic dependent on states established by the master-slave registers. The clock circuitry is configured to clock the master portion of the master-slave registers with a lag rendering of a clock signal and to clock the slave portion of the registers with a lead rendering of the clock signal. In a particular example, the circuitry may define a frequency divider of a complementary CMOS realization.
    Type: Grant
    Filed: July 31, 2006
    Date of Patent: August 12, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventor: Xiang Zhu
  • Publication number: 20080186070
    Abstract: A latch or flip flop circuit with an increased operating frequency is disclosed. In particular, the operating frequency of the latch is increased by reducing the set up time of the latch circuit. A regenerative circuit is provided between the transmission gate of the latch circuit and the data output. The regenerative circuit comprises a pull up circuit and a pull down circuit. The circuit arrangement of the present invention may be applied to flip flop or latch circuits in combination with other flip flop or latch circuits such as a Master-Slave configuration.
    Type: Application
    Filed: April 27, 2006
    Publication date: August 7, 2008
    Inventors: Arun Sundaresan Iyer, Abhishek Kumar, Zahir Parkar
  • Patent number: 7408393
    Abstract: A master-slave flip-flop comprises master and slave latches, with the data output of the master latch connected to the data input of the slave latch. The latches receive clock signals CKM and CKS at their respective clock inputs; each latch is transparent when its clock signal is in a first state and latches a signal applied to its input when its clock signal is in a second state. A clock buffer receives an input clock CKin and generates nominally complementary clock signals CKM and CKS such that one latch is latched while the other is transparent. The clock buffer is arranged to skew CKS with respect to CKM such that the slave latch is made transparent earlier than it would without the skew, making the minimum delay (tpd) between the toggling of CKin and a resulting change at the slave latch's output less than it would otherwise be.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: August 5, 2008
    Assignee: Inphi Corporation
    Inventors: Dhruv Jain, Gopal Raghavan, Jeffrey C. Yen, Carl W. Pobanz
  • Patent number: 7405605
    Abstract: Data storage circuits and components of such circuits constructed using nanotube switching elements. The storage circuits may be stand-alone devices or cells incorporated into other devices or circuits. The data storage circuits include or can be used in latches, master-slave flip-flops, digital logic circuits, memory devices and other circuits. In one aspect of the invention, a master-slave flip-flop is constructed using one or more nanotube switching element-based storage devices. The master storage element or the slave storage element or both may be constructed using nanotube switching elements, for example, using two nanotube switching element-based inverters. The storage elements may be volatile or non-volatile. An equilibration device is provided for protecting the stored data from fluctuations on the inputs. Input buffers and output buffers for data storage circuits of the invention may also be constructed using nanotube switching elements.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: July 29, 2008
    Assignee: Nantero, Inc.
    Inventor: Claude L. Bertin
  • Patent number: 7405606
    Abstract: A D flip-flop with a reduced power product or reduced clock line capacitance is disclosed. The flip-flop includes a half-static slave stage or a master stage with clock gating by the input and output. The half-static slave stage an output inverter and a feedback element consisting of a single switching transistor having a gate connected to the output of the flip-flop and the input of the inverter as its load. The clock gating circuit, which may comprise an XNOR gate, reduces the frequency of switching events by permitting clock pulses to pass into the master or slave stage only when the input and output of the flip-flop are at the same logical state.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: July 29, 2008
    Assignee: Intellectual Ventures Fund 27 LLC
    Inventors: Chi Wah Kok, Yee Ching Tam
  • Patent number: 7401279
    Abstract: Each of D flip-flops (FFs) 13a to 13f constituting a scan path circuit has a normal operation input circuit to be selected in a normal operation and a test operation input circuit to be selected in a test operation, and a control signal having an intermediate voltage between a supply voltage and a ground voltage is sent from a voltage generating circuit 17 to the test operation input circuit of each FF in the test operation. In this case, the amount of an output change in data in each FF is smoother than that in the case in which the supply voltage is applied. Consequently, the delay time of the data is increased. The intermediate voltage to be applied to each FF in the test operation is determined based on a feedback signal sent from a test circuit 15 for checking whether scanned-out data have an error or not.
    Type: Grant
    Filed: August 21, 2006
    Date of Patent: July 15, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masaya Sumita, Akira Miyoshi
  • Patent number: 7401278
    Abstract: A binary latch that operates as an edge-triggered flip-flop and which is LSSD-testable that comprises an edge triggered master. The binary latch comprises an edge triggered master flip-flop (2), with a clock input connected to the system clock (SYS_CLK), with a data input (DI) and with an output (DO), a level sensitive scan design (LSSD) slave latch (3), connected to the output (DO) of the master flip-flop (2), a NAND gate (4) with a first input (41) connected to the system clock (SYS_CLK), a second input (42) connected to a test input (TEST) and with an output (43) connected to the LSSD slave latch clock input (LSSD_clk).
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: July 15, 2008
    Assignee: International Business Machines Corporation
    Inventor: Peter Verwegen
  • Patent number: 7391249
    Abstract: Provided is a multi-threshold complementary metal oxide semiconductor (MTCMOS) latch circuit including: a data inverting circuit for inverting and outputting input data under the control of a sleep control signal; a transmission gate for transferring the data signal output from the data inverting circuit under the control of a clock control signal; a signal control circuit for outputting the data signal output from the transmission gate under the control of a reset control signal and the sleep control signal; and a feedback circuit for feeding back the signal output from the signal control circuit and preserving the data in a sleep mode. The MTCMOS latch circuit can minimize power consumption caused by a leakage current due to elements scaled down to nano scale and also contribute to high-speed operation of a logic circuit by using an element having a low threshold voltage.
    Type: Grant
    Filed: December 1, 2006
    Date of Patent: June 24, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Dae Woo Lee, Yil Suk Yang, Gyu Hyun Kim, Soon Il Yeo, Jong Dae Kim
  • Patent number: 7378890
    Abstract: Several latch circuits including a NAND gate stage and combinations of clocked inverter stages and inverter stages are described. A programmable frequency divider including homologue frequency divider circuits using the latch circuits is also described. Also described is a circuit included in the homologue frequency divides and a method for correcting the duty cycle of clock signals generated by the homologue frequency dividers to 50%.
    Type: Grant
    Filed: September 19, 2007
    Date of Patent: May 27, 2008
    Assignee: International Business Machines Corporation
    Inventors: John S. Austin, Ram Kelkar, Pradeep Thiagarajan
  • Patent number: 7375568
    Abstract: In the present invention, a logic circuit is provided therein with a current supply control circuit for controlling the amount of current supplied to a differential circuit. This current supply control circuit comprises a bypass path for bypassing the current around the differential circuit, a switching transistor interposed in the bypass path for opening/closing the bypass path in accordance with the signal level of a clock signal applied thereto from the outside, and a current amount control transistor for controlling the amount of current supplied to the differential circuit. The current amount control transistor adjusts the amount of current in accordance with the signal level of the clock signal.
    Type: Grant
    Filed: June 16, 2004
    Date of Patent: May 20, 2008
    Assignee: NEC Corporation
    Inventor: Yasushi Amamiya
  • Patent number: 7373572
    Abstract: In one embodiment, an apparatus includes a system pulse latch to generate at least one system latch signal in response to a data input signal and a pulsed system clock signal; a shadow pulse latch to generate at least one shadow latch signal in response to the data input signal and the pulsed system clock signal; and an output joining circuit, coupled to the system pulse latch and the shadow pulse latch, to provide a data output signal in response to the at least one system latch signal and the at least one shadow latch signal.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: May 13, 2008
    Assignee: Intel Corporation
    Inventors: Tak M. Mak, Ming Zhang, Subhasish Mitra, Paul E. Shipley
  • Patent number: 7362153
    Abstract: In some embodiments, a receiver latch circuit, includes a dynamic latch having at least one input terminal to receive an input data signal and at least one latch terminal. The dynamic latch is adapted to generate an amplified output data signal based at least in part on the input data signal. The dynamic latch includes at least one capacitor, coupled between the at least one input terminal and the at least one latch terminal, to reduce intersymbol interference in the input data signal.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: April 22, 2008
    Assignee: Intel Corporation
    Inventor: Taner Sumesaglam
  • Patent number: 7362154
    Abstract: A programmable phase frequency divider for space applications is implemented in CMOS technology, and consists of three radiation hardened D-type flip flops and combinational logic circuits to provide the feedback controls that allow programmable frequency division ratios from 1 to 8. The radiation hardened D-type flip flop circuits are designed to keep on running properly at GHz frequencies even after a single event upset (SEU) hit. The novel D-type flip flop circuits each have two pairs of complementary inputs and outputs to mitigate SEU's. The combinational logic circuits are designed to utilize the complementary outputs in such a way that only one of the four dual complementary inputs to any D-type flip flop gets flipped at most after an SEU hit. Therefore, a radiation hardened programmable phase frequency divider that is immune to SEU's is achieved.
    Type: Grant
    Filed: May 18, 2006
    Date of Patent: April 22, 2008
    Assignee: International Business Machines Corporation
    Inventor: William Yeh-Yung Mo
  • Patent number: 7358786
    Abstract: A control signal generator, latch circuit, flip-flop and method for controlling operations in the flip-flop may be configured so as to efficiently perform latching and scanning operations in the flip-flop. The control signal generator may generate at least two pulses based on a scan enable signal being received in a first state and on a received clock signal, and may generate at least two internal clock signals based on the received clock signal, and based on the scan enable signal being received in a second state. The latch circuit may latch a received input signal based on the at least two pulses and may latch a received scan input signal based on the at least two internal clock signals.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: April 15, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Min-Su Kim
  • Patent number: 7358787
    Abstract: A dual purpose current mode logic (“CML”) latch circuit is provided which includes a CML latch operable to receive at least a pair of differential input data signals and at least one clock signal. The CML latch is operable to generate at least one output signal in accordance with the states of the pair of input differential data signals. A mode control device is operable to receive a mode control signal to operate the CML latch as a buffer or as a latch. In such way, when the mode control signal is inactive, the CML latch generates and latches the output signal at a timing determined by the at least one clock signal, and when the mode control signal is active the CML latch generates the output signal such that the output signal changes whenever the states of the pair of differential input data signals change.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: April 15, 2008
    Assignee: International Business Machines Corporation
    Inventors: Joseph O. Marsh, Joseph Natonio, James M. Wilson
  • Patent number: 7345520
    Abstract: In a circuit in which a signal arrival time with respect to a register is different in accordance with the change of a delay time of the circuit, a mechanism capable of adjusting a clock signal of the register is previously provided to deal with the case in which a set-up time in the register is not satisfied due to an increase of the delay time, and the delay time of the clock signal is changed in response to the change of the delay time of the circuit in respective modes. Thereby, the set-up time of data in the register can be satisfied, and an operation frequency of the circuit can be prevented from lowering.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: March 18, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Takanori Isono
  • Patent number: 7342429
    Abstract: Several latch circuits including a NAND gate stage and combinations of clocked inverter stages and inverter stages are described. A programmable frequency divider including homologue frequency divider circuits using the latch circuits is also described. Also described is a circuit included in the homologue frequency divides and a method for correcting the duty cycle of clock signals generated by the homologue frequency dividers to 50%.
    Type: Grant
    Filed: January 5, 2006
    Date of Patent: March 11, 2008
    Assignee: International Business Machines Corporation
    Inventors: John S. Austin, Ram Kelkar, Pradeep Thiagarajan