Master-slave Bistable Latch Patents (Class 327/202)
  • Publication number: 20100019815
    Abstract: A circuit having a local power block for leakage reduction is disclosed. The circuit has a first portion and a second portion. The first portion is configured to operate at a substantially greater operating frequency than the operating frequency of the second portion. The second portion has a local power block configured to decouple the second portion if the second portion is inactive to reduce leakage current associated with the second portion without sacrificing performance of the first portion.
    Type: Application
    Filed: October 6, 2009
    Publication date: January 28, 2010
    Applicant: QUALCOMM INCORPORATED
    Inventors: Fadi Adel Hamdan, Anthony D. Klein
  • Patent number: 7649393
    Abstract: A semiconductor integrated circuit has an active mode and a sleep mode. The semiconductor integrated circuit is constructed by alternately connecting a plurality of combinational logic circuits and a plurality of flip-flops. The flip-flops include a retention flip-flop that is supplied with electric power and retains the data in the sleep mode, and a non-retention flip-flop that is not supplied with electric power during the sleep mode. The non-retention flip-flop includes an initializing circuit that initializes the non-retention flip-flop when the semiconductor integrated circuit is switched from the sleep mode to the active mode.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: January 19, 2010
    Assignee: Kawasaki Microelectronics, Inc.
    Inventor: Tasuku Maeda
  • Patent number: 7649395
    Abstract: A scan flip-flop circuit including a data input, a scan input, a data output, a flip-flop, a multiplexer and a delay element is provided. The multiplexer allows selection of either the scan input or the data input for presentation at the input of the flip-flop. The flip-flop provides an output signal at the output of the scan flip-flop. The delay element is in a signal path between the scan input and the input of the flip-flop, and provides a signal propagation delay between the scan input and the input of the flip-flop. The delay between the scan input and the input of the flip-flop is substantially larger than the signal propagation delay between the data input and the input of the flip-flop. The delay in the scan path reduces the need for external buffers to avoid hold-time violations during scan testing of integrated circuits.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: January 19, 2010
    Assignee: ATI Technologies ULC
    Inventor: Rubil Ahmadi
  • Publication number: 20100007396
    Abstract: A compound logic flip-flop. The flip-flop includes a plurality of input stages, wherein each of the input stages is coupled to receive at least one input signal and a clock signal. Each of the plurality of input (i.e. ‘master’) stages is configured to perform a corresponding input logic function during a first phase of a clock cycle and to store a result of the corresponding input logic function. The flip-flop further includes an output (i.e. ‘slave’) stage coupled to receive the clock signal and the results of the input logic functions from each of the plurality of input stages. The output stage is configured, during a second phase of the clock cycle, to logically combine the results of the input logic functions by performing an output logic function and provide an output signal based on a result of the output logic function.
    Type: Application
    Filed: July 11, 2008
    Publication date: January 14, 2010
    Inventor: Daniel W. Bailey
  • Publication number: 20100001774
    Abstract: A disclosed embodiment is a data retention flip flop comprising master and slave circuits that are configured to be turned off when a single sleep mode signal is activated. The disclosed embodiment also comprises an always-on balloon circuit coupled to the master circuit, where the always-on balloon circuit includes a common sub-circuit shared with the master circuit. The master circuit writes into the always-on balloon circuit when the single sleep mode signal is activated, and the master circuit reads from the always-on balloon circuit when the single sleep mode signal is deactivated. The always-on balloon circuits comprises high threshold voltage transistors, while the slave circuit comprises low threshold voltage transistors. The master and slave circuits have no leakage current, or substantially no leakage current, after the single sleep mode signal is activated.
    Type: Application
    Filed: July 3, 2008
    Publication date: January 7, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: Gregory Djaja, Karthik Chandrasekharan
  • Patent number: 7644328
    Abstract: A device shares an existing test signal routing trace with an alternative power supply delivery channel to portions of registers located in combinatorial logic sections.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: January 5, 2010
    Assignee: Intel Corporation
    Inventor: Soon Seng Seh
  • Patent number: 7639056
    Abstract: In a method and system for data retention, a data input is latched by a first latch. A second latch coupled to the first latch receives the data input for retention while the first latch is inoperative in a standby power mode. The first latch receives power from a first power line that is switched off during the standby power mode. The second latch receives power from a second power line. A controller receives a clock input and a retention signal and provides a clock output to the first latch and the second latch. A change in the retention signal is indicative of a transition to the standby power mode. The controller continues to hold the clock output at a predefined voltage level and the second latch continues to receive power from the second power line in the standby power mode, thereby retaining the data input.
    Type: Grant
    Filed: May 26, 2005
    Date of Patent: December 29, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Sumanth Katte Gururajarao, Hugh T. Mair, David B. Scott, Uming Ko
  • Publication number: 20090315603
    Abstract: A method and a circuit for detecting a disturbance of a state of at least one first flip-flop from a group of several first flip-flops of an electronic circuit, wherein: the respective outputs of the first flip-flops in the group are, independently from their functional purpose, combined to provide a signal and its inverse, triggering two second flip-flops having data inputs forced to a same state, the respective outputs of the second flip-flops being combined to provide the result of the detection; and a pulse signal comprising a pulse at least for each triggering edge of one of the first flip-flops in the group initializes the second flip-flops.
    Type: Application
    Filed: May 16, 2008
    Publication date: December 24, 2009
    Applicant: STMicroelectronics (Rousset) SAS
    Inventors: Frederic Bancel, David Hely, Nicolas Berard
  • Publication number: 20090309641
    Abstract: An edge triggered flip-flop including at least one inverter and at least one transmission gate section. Each transmission gate section includes an upper part having a first transmission gate and a second transmission gate connected in series, the first transmission gate being controlled in accordance with a clock signal, and the second transmission gate being controlled in accordance with an enable clock signal. Each transmission gate section also includes a lower part having a third transmission gate and a fourth transmission gate connected in series, the third transmission gate being controlled complementarily to the first transmission gate in accordance with the clock signal, and the fourth transmission gate being controlled complementarily to the second transmission gate in accordance with the enable clock signal.
    Type: Application
    Filed: June 10, 2009
    Publication date: December 17, 2009
    Inventor: Woo-Hyun Park
  • Publication number: 20090309640
    Abstract: A semiconductor integrated circuit having a flip-flop with improve soft error resistance, including a controller which controls a clock signal generating circuit to output a first clock signal and a second clock signal with a timing so that logic of data retained in a first data retaining terminal becomes identical to logic of data retained in a third data retaining terminal, and then turns on a first switching circuit to connect between the first data retaining terminal and the first data retaining terminal.
    Type: Application
    Filed: June 15, 2009
    Publication date: December 17, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventor: Takayuki MIYAZAKI
  • Patent number: 7634749
    Abstract: A method of designing a skew insensitive circuit is performed by designing a synchronous circuit including flip-flops and combinatorial logic and, for each flip-flop, inserting logic gates to receive a skewed clock signal and to locally derive non-overlapping clock phases from the skewed clock signal.
    Type: Grant
    Filed: April 1, 2005
    Date of Patent: December 15, 2009
    Assignee: Cadence Design Systems, Inc.
    Inventors: Jordi Cortadella, Alex Kondratyev, Luciano Lavagno
  • Publication number: 20090295436
    Abstract: A master stage 101 comprises a differential circuit composed of transistors 1 and 2, a differential circuit composed of transistors 3 and 4, a differential circuit composed of transistors 5 and 6, a load circuit 7 (a first load circuit), a load circuit 8 (a second load circuit), and a current source transistor 9. The load circuit 7 (the first load circuit) is composed of an inductor 7A (a first inductor), an inductor 7B (a fifth inductor), and a capacity 7C (a first capacity). The inductor 7B and capacity 7C cooperates together in forming a parallel resonance circuit (a first LC parallel resonance circuit), while the parallel resonance circuit is connected in series to the inductor 7A.
    Type: Application
    Filed: September 1, 2006
    Publication date: December 3, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Yoshifumi Hosokawa, Noriaki Saito, Yoshito Shimizu
  • Patent number: 7626434
    Abstract: In general, in one aspect, the disclosure describes an apparatus comprising a low leakage latch to store a state of a circuit during inactive periods. The state is transferred to the low leakage latch upon receipt of an inactive pulse. A buffer is used to receive the state from an output of the low leakage latch and to isolate the state. State restore circuitry is used to restore the state to the circuit when the circuit returns to an active mode. The state restore circuitry is used to receive the isolated state and to restore the state upon receipt of an active pulse.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: December 1, 2009
    Assignee: Intel Corporation
    Inventor: Randy J. Aksamit
  • Patent number: 7626433
    Abstract: A flip-flop circuit arrangement having a total of four differential amplifiers (1, 2, 3, 4), which are connected to one another to produce a D flip-flop, is specified. According to the suggested principle, the two shared emitter nodes (E1, E2) of the differential amplifiers (1, 2, 3, 4) are connected via a switch pair (S1, S2) to supply potential and are activated by a differential input clock signal at a control input (CN, CP). The present flip-flop circuit is operable using especially low supply voltage (VCC) and is preferably suitable for constructing frequency dividers or shift registers.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: December 1, 2009
    Assignee: Austriamicrosystems AG
    Inventor: Wolfgang Hoess
  • Publication number: 20090290434
    Abstract: A dual function serial and parallel data register with integrated program verify functionality. The master and slave latching circuits of the dual function data register can concurrently store two different words of data. In a program verify operation, the master latch stores program data and the slave latch will receive and store read data. Comparison logic in each register stage will compare the data of both latches, and integrate the comparison result to that of the previous register stage. The final single bit result will indicate the presence of at least one bit that has not been programmed. Automatic program inhibit logic in each stage will prevent successfully programmed bits from being re-programmed in each subsequent reprogram cycle. Either data word can be serially clocked out by selectively starting the shift operations on either the low or high active logic level of a clock signal.
    Type: Application
    Filed: December 20, 2007
    Publication date: November 26, 2009
    Applicant: SIDENSE CORP.
    Inventor: Wlodek Kurjanowicz
  • Patent number: 7622976
    Abstract: The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: November 24, 2009
    Assignee: STC.UNM
    Inventors: Lawrence T. Clark, John K. McIver, III
  • Patent number: 7622975
    Abstract: A circuit having a local power block for leakage reduction is disclosed. The circuit has a first portion and a second portion. The first portion is configured to operate at a substantially greater operating frequency than the operating frequency of the second portion. The second portion has a local power block configured to decouple the second portion if the second portion is inactive to reduce leakage current associated with the second portion without sacrificing performance of the first portion.
    Type: Grant
    Filed: July 10, 2007
    Date of Patent: November 24, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Fad Ad Hamdan, Anthony D. Klein
  • Patent number: 7616040
    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: Grant
    Filed: October 23, 2007
    Date of Patent: November 10, 2009
    Assignee: Sony Corporation
    Inventor: Tetsuo Motomura
  • Patent number: 7616041
    Abstract: A circuit is disclosed for retaining a signal value during a sleep mode while a portion of said circuit is powered down comprising: a clock signal input operable to receive a clock signal; at least one latch clocked by said clock signal; a data input, a data output and a forward data path therebetween, wherein a signal value is operable to be received at said data input, is clocked through said at least one latch and passes to said data output along said forward data path; at least one of said at least one latch comprises a retention latch operable to retain a signal value during said sleep mode, said retention latch not being located on said forward data path; and a tristateable device, said tristateable device being arranged between said forward data path and said retention latch and being operable to selectively isolate said retention latch from said forward data path in response to receipt of a first sleep signal; wherein in response to receipt of a second sleep signal, said second sleep signal being rece
    Type: Grant
    Filed: September 19, 2008
    Date of Patent: November 10, 2009
    Assignee: ARM Limited
    Inventors: Marlin Frederick, Jr., James David Shiffer, III
  • Patent number: 7613969
    Abstract: A method and system for clock skew independent scan chains. In one embodiment, a method comprises connecting a plurality of mux-D scan registers in a chain configuration, wherein a first mux-D scan register of the plurality is associated with a first clock network, and a second mux-D scan register of the plurality is associated with a second clock network. The plurality of mux-D scan registers have a scan mode. The first mux-D scan register and the second mux-D scan register become clock skew independent by controlling a scan-enable signal and a clock signal.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: November 3, 2009
    Assignee: Cadence Design Systems, Inc.
    Inventor: Sandeep Bhatia
  • Patent number: 7612594
    Abstract: A latch circuit includes first, second, and third inverter circuits, a switching element, and a capacitor element. The first inverter circuit and the second inverter circuit are cross-connected to each other. The third inverter circuit logically inverts an output from the first inverter circuit. The switching element is connected between the output terminal of the second inverter circuit and the output terminal of the third inverter circuit. The capacitor element is connected between the output terminal of the third inverter circuit and a reference voltage node.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: November 3, 2009
    Assignee: Panasonic Corporation
    Inventor: Kouhei Fukuoka
  • Publication number: 20090267671
    Abstract: Disclosed is a technique for providing minimal sequential overhead in a flip-flop circuit. Equalization of setup times is achieved in one embodiment. In addition, delays in clock to Q can be equalized for both rising data transitions and falling data transitions. Large setup times are not required since optimization techniques equalize setup times for both rising and falling data transitions.
    Type: Application
    Filed: April 29, 2008
    Publication date: October 29, 2009
    Inventor: Jeffrey Scott Brown
  • Publication number: 20090267672
    Abstract: A serial peripheral interface (SPI) circuit and a display using the same are provided. The SPI circuit includes a mater device and a slave device. A serial data input pin and a serial data output pin of the slave device are both electrically connected to a data input/output pin of the master device. When a read instruction is sent from the master device to the slave device, the master device is set in a read status, and the slave device outputs data to the master device via the serial data output pin in response to the read instruction. When a write instruction is sent from the master device to the slave device, the master device is set in a write status, and writes data to the slave device via the serial data input pin thereof in response to the write instruction.
    Type: Application
    Filed: November 20, 2008
    Publication date: October 29, 2009
    Applicant: NOVATEK MICROELECTRONICS CORP.
    Inventor: Chien-Chuan Liao
  • Publication number: 20090256596
    Abstract: A flip-flop, and a frequency divider and an RF circuit using the flip-flop. The frequency divider, which receives a first signal and generates a second signal by dividing a frequency of the first signal, including a plurality of flip-flops that each latch and output a signal based on the first signal; and at least one switch unit that is switched in response to a control signal to modify a signal transfer path between the plurality of the flip-flops, wherein a different number of flip-flops are activated in response to each first and second status of the control signal so that the frequency of the first signal is divided by different multiples.
    Type: Application
    Filed: March 10, 2009
    Publication date: October 15, 2009
    Inventor: Hyoung-seok Oh
  • Publication number: 20090256608
    Abstract: A disclosed embodiment is a low leakage data retention flip flop comprising a master circuit for retaining data during sleep mode, wherein the master circuit is configured to receive a reduced supply voltage during the sleep mode. The flip flop includes a slave circuit having low threshold voltage transistors, where the slave circuit is turned off during the sleep mode. In various embodiments, the master circuit might utilize high threshold voltage, standard threshold voltage, or low threshold voltage transistors. Similarly, the slave circuit might utilize high threshold voltage, standard threshold voltage, or low threshold voltage transistors. To begin the sleep mode, the master circuit receives a reduced supply voltage and the slave circuit is coupled to ground and is thus turned off. During the sleep mode, the slave circuit experiences virtually no leakage current, and the master circuit experiences a reduced leakage current.
    Type: Application
    Filed: April 10, 2008
    Publication date: October 15, 2009
    Applicant: BROADCOM CORPORATION
    Inventors: Gregory Djaja, Mark Slamowitz, Karthik Chandrasekharan
  • Patent number: 7602217
    Abstract: A level shifter circuit and method of operating therefor. The level shifter circuit is coupled to receive a data signal via an input circuit, wherein the input circuit is in a first voltage domain. The level shifter circuit is also coupled to receive a clock signal from a second voltage domain. On a first portion of the clock cycle, true and complementary output nodes of the level shifter circuit (which are in the second voltage domain) are pulled to a first voltage by activation of respective pull transistors. On a second portion of the clock cycle, one of the true or complementary output nodes is pulled to a second voltage on a second voltage node by enabling the supply to the latch. Data is captured by the keeper, outputting true and complementary versions of the data signal in the second phase of the clock.
    Type: Grant
    Filed: August 16, 2007
    Date of Patent: October 13, 2009
    Assignee: GLOBALFOUNDRIES Inc.
    Inventor: Calvin Watson
  • Publication number: 20090251185
    Abstract: A data retention device includes a first latch disposed between a data input terminal and a data output terminal for storing a data signal received from the data input terminal and transmitting the data signal through a data forward path to the data output terminal according to a clock signal in an operational mode; a second latch disposed in a branch of the data forward path between the first latch and the data output terminal for receiving the data signal in the operational mode and retaining the data signal in a sleep mode; and a first tri-state buffer disposed in the data forward path between the first latch and the branched second latch and enabled to conduct the data forward path in the operational mode and disabled to cut off the data forward path in the sleep mode according to a data retention signal.
    Type: Application
    Filed: April 1, 2009
    Publication date: October 8, 2009
    Applicant: FARADAY TECHNOLOGY CORPORATION
    Inventors: JENG-HUANG WU, CHIH-WEN YANG
  • Patent number: 7600167
    Abstract: A flip-flop has a first latch and a second latch. The first latch has a first feedback circuit and a first selecting circuit which selects one of a first data input signal and an output signal of the first feedback circuit, based on the logic level of a first clock signal. The second latch has a second feedback circuit and a second selecting circuit which selects an output signal of the first latch and an output signal of the second feedback circuit based on the inverted logic level in case of the first latch. The first feedback circuit has a third selecting circuit which selects one of an output signal of the first latch and a second data input signal based on the logic level of a second clock signal, and outputs a signal selected by the third selecting circuit to the first selecting circuit.
    Type: Grant
    Filed: March 27, 2007
    Date of Patent: October 6, 2009
    Assignee: NEC Corporation
    Inventor: Hiroaki Shoda
  • Patent number: 7596732
    Abstract: A digital storage element (e.g., a flip-flop or a latch) includes a master transparent latch that receives functional data from a data input port and scan data from a scan input port and a slave transparent latch coupled to the master transparent latch. The slave transparent latch includes dedicated functional data and scan data output ports. The digital storage element operates in a functional mode and in a scan mode. While in the scan mode, a first clock signal is used by the slave transparent latch and a second clock signal is used by the master transparent latch. The first and second clock signals are non-overlapping and, as such, avoid the digital storage element from creating hold violations.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: September 29, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Charles M. Branch, Steven C. Bartling, Dharin N. Shah
  • Publication number: 20090231008
    Abstract: A flip-flop circuit operates by a first clock signal whose amplitude is smaller than that of input data D. A pair of transistors receive the input data D and the reversed input data *D, respectively, to latch the input data D. An activation circuit activates the pair of transistors in a conduction state. A control circuit receives the first clock signal and sets the activation circuit to a conduction state for a predetermined time period starting from an edge timing of the received first clock signal. The control circuit increases the amplitude of the first clock signal and sets the activation circuit in a conduction state by using a second clock signal which is the first clock signal with the increased amplitude.
    Type: Application
    Filed: February 13, 2009
    Publication date: September 17, 2009
    Inventors: Satoru Sekine, Shinji Furuichi
  • Patent number: 7583121
    Abstract: A flip-flop includes a master latch, a first inverter, a slave latch, and a first clocked inverter. The master latch has an input for receiving an input signal and an output. The first inverter has an input coupled to the output of the master latch and an output for providing an output of the flip-flop. The slave latch is directly connected to the input of the first inverter. The first clocked inverter has an input directly connected to the slave latch and an output coupled to the master latch.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: September 1, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Matthew S. Berzins, Charles A. Cornell, Samuel J. Tower
  • Patent number: 7576583
    Abstract: Disclosed are a latch circuit and a flip-flop circuit, which are capable of suppressing occurrence of a single-event effect, and, in the event of a single-event transient (SET), elimination adverse effects thereof on the circuit. The latch circuit comprises a dual-port inverter, and a dual-port clocked inverter including no transmission gate to reduce a region of strong electric field to be formed. A delay time is set up in a clock to eliminate adverse effects of the SET, and a leading-edge delayed clock to be entered into one of two storage nodes is generated in such a manner as to delay a transition of the storage node and the entire storage nodes from a latch mode to a through mode while preventing an increase in hold time due to the delay time.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: August 18, 2009
    Assignees: Japan Aerospace Exploration Agency, High-Reliability Engineering & Components Corporation
    Inventors: Satoshi Kuboyama, Hiroyuki Shindou, Yoshiya Ilde, Akiko Makihara
  • Patent number: 7576582
    Abstract: Provided is a low-power clock gating circuit using a Multi-Threshold CMOS (MTCMOS) technique. The low-power clock gating circuit includes a latch circuit of an input stage and an AND gate circuit of an output stage, in which power consumption caused by leakage current in the clock gating circuit is reduced in a sleep mode, and supply of a clock to a unused device of a targeted logic circuit is prevented by the control of a clock enable signal in an active mode, thereby reducing power consumption. The low-power clock gating circuit using an MTCMOS technique uses devices having a low threshold voltage and devices having a high threshold voltage, which makes it possible to implement a high-speed, low-power circuit, unlike a conventional clock gating circuit using a single threshold voltage.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: August 18, 2009
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Dae Woo Lee, Yil Suk Yang, Ik Jae Chun, Chun Gi Lyuh, Tae Moon Roh, Jong Dae Kim
  • Publication number: 20090201063
    Abstract: A dynamic semiconductor device is provided with a plurality of master step sections having hatch sections for temporarily storing input data and dynamic gate sections; a plurality of slave step sections, which are alternately connected with master step sections and provided with dynamic gate sections or with latch sections and dynamic gate sections; and a timing signal generating section for generating a signal for controlling operation of the master step sections and the slave step sections. The timing signal generating section supplies the latch sections with signals for storing data of the previous step before the data is erased.
    Type: Application
    Filed: December 28, 2006
    Publication date: August 13, 2009
    Applicant: NEC CORPORATION
    Inventors: Masahiro Nomura, Yoshifumi Ikenaga, Koichi Takeda
  • Publication number: 20090189664
    Abstract: A circuit has first latch, a second latch, a coupling circuit, and a power down circuit. The first latch has an input/output coupled to a data node. The second latch has an input/output. The coupling circuit is coupled between the input/output of the second latch and the data node. The coupling circuit is enabled during a normal operation of the circuit and disabled during a power down mode of the circuit. The power down control circuit is for disabling the first latch during the power down mode and for a time period after a transition from the power down mode to the normal operation. This allows the second latch to set the state of the first latch when transitioning from the power down mode to the normal mode. Thus normal operation can be fast, and the power down mode can have low leakage current.
    Type: Application
    Filed: January 30, 2008
    Publication date: July 30, 2009
    Inventor: Scott I. Remington
  • Patent number: 7560964
    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: March 18, 2005
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: David E. Lackey, Steven F. Oakland, Peter Verwegen
  • Patent number: 7560966
    Abstract: A method of testing connectivity through a plurality of dual purpose current mode logic (“CML”) latch circuits connected in a series is provided. Each of the CML latch circuits are operable to latch at least one output signal at a timing in accordance with at least one clock signal and having a mode control device for operating the CML latch circuit as a buffer amplifier when the at least one clock signal is inactive. The method comprises the steps of activating the mode control devices of each of the CML latches to operate each of the CML latches as a buffer; inputting a first signal to a first CML latch of the series; latching an output signal of a second CML latch of the series, the second CML latch being connected at a point in the series downstream from the first CML latch; and determining whether the output signal changes in accordance with a change in the first signal.
    Type: Grant
    Filed: December 19, 2007
    Date of Patent: July 14, 2009
    Assignee: International Business Machines Corporation
    Inventors: Joseph O. Marsh, Joseph Natonio, James M. Wilson
  • Patent number: 7560965
    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: Grant
    Filed: April 30, 2007
    Date of Patent: July 14, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Jeffrey W. Waldrip, Alexander B. Hoefler
  • Patent number: 7548102
    Abstract: The present invention provides a latch circuit that is operable to generate a pulse from first and second clock signals to allow gates in a datapath to propagate data with minimal latency. The first clock signal is a version of the system clock and the second control signal is a time-shifted, inverted version of the system clock signal. Each of the individual latches in a datapath comprises data propagation logic. In one embodiment of the invention, the data propagation logic uses the first and second clock signals to generate an “implicit” pulse. In another embodiment of the invention, the data propagation logic uses the first and second clock signals to generate an “explicit” pulse. The implicit and explicit pulses are used to control the transmission gate of the latch to provide propagation of data through the latch with minimal latency.
    Type: Grant
    Filed: July 14, 2006
    Date of Patent: June 16, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ravindraraj Ramaraju, Ambica Ashok, Cody B. Croxton, Peter M. Ippolito, Prashant U. Kenkare
  • Patent number: 7548103
    Abstract: A storage device and methods thereof are disclosed. The device includes a clock control module and a latch. During normal operation, the clock control module provides a periodic clock signal to a clock input of the latch, allowing the latch to operate normally. In a low power mode of operation, the clock control module provides a constant signal to the clock input of the latch so that the latch retains stored data during the low power mode of operation. The storage device can also include a power control module that provides a first power level to the latch in the normal mode of operation and a second power level during the second mode of operation.
    Type: Grant
    Filed: October 26, 2006
    Date of Patent: June 16, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Ravindraraj Ramaraju, David R. Bearden
  • Patent number: 7545185
    Abstract: The present invention improves a frequency divider circuit so that the frequency divider further obtains a capability of operating an injection-locking frequency division without changing or adding any component; and, the frequency divider operates under low voltage and low power consumption yet in high frequency, where the present invention can be use in related fields of radio frequency and optoelectronic communication.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: June 9, 2009
    Assignee: National Central University
    Inventors: Yi-Jen Chan, Fan-Hsiu Huang, Dong-Ming Lin
  • Patent number: 7543205
    Abstract: A system of control signal synchronization of a scannable storage circuit includes any number of storage circuits interconnected together with logic circuitry to form at least a portion of a functional circuit. Each of the storage circuits may include an input transmission gate to apply any one of a data input and a scan input to a storage element of the storage circuit based on an input circuitry that considers the state of the scan enable signal and a timing signal of a clock associated with the storage element. In addition, a control signal in a master latch of the storage element may synchronously close a hold loop in the master latch when the input transmission gate is opened upon the timing signal of the clock transitioning to a different state.
    Type: Grant
    Filed: April 27, 2006
    Date of Patent: June 2, 2009
    Assignee: Texas Instruments Incorporated
    Inventor: Kumar Abhishek
  • Publication number: 20090128210
    Abstract: An electric circuit has a first differential circuit for transmitting input data to a first node, a second differential circuit for holding the first node data, a first clock transmission circuit for flowing a first current in accordance with a clock signal, and a first transformer circuit for transformer-coupling the first differential circuit with the first clock transmission circuit, and the second differential circuit with the first clock transmission circuit.
    Type: Application
    Filed: November 12, 2008
    Publication date: May 21, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Takuji YAMAMOTO
  • Patent number: 7535259
    Abstract: A threshold voltage of a transistor is fluctuated because of fluctuation in film thickness of a gate insulating film or in gate length and gate width caused by differences of used substrates or manufacturing steps. In order to solve the problem, according to the present invention, there is provided a clocked inverter including a first transistor and a second transistor connected in series, and a compensation circuit including a third transistor and a fourth transistor connected in series.
    Type: Grant
    Filed: December 5, 2007
    Date of Patent: May 19, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Mitsuaki Osame, Aya Anzai
  • Publication number: 20090108896
    Abstract: It is made possible to provide a flip-flop circuit capable of implementing the error correction function with a small area increase as far as possible and a pipeline system using such a flip-flop circuit. A flip-flop circuit includes: a flip-flop configured to operate based on a rising edge or a falling edge of a first clock signal; a decision circuit configured to compare an input of the flip-flop with an output thereof and output a request signal when the input of the flip-flop is different from the output thereof; and a control circuit configured to receive a second clock signal from outside and generate the first clock signal and a confirmation signal. When the request signal is sent from the decision circuit after the flip-flop has been activated, the control circuit inverts the first clock signal, sends the confirmation to the decision circuit, and makes the decision circuit cancel the request signal.
    Type: Application
    Filed: September 24, 2007
    Publication date: April 30, 2009
    Inventors: Shinichi Yasuda, Keiko Abe
  • Publication number: 20090108885
    Abstract: A design structure including a CMOS rail-to-rail differential latch is provided in which a plurality of cross-coupled devices pull first and second nodes of the latch to opposite rail-to-rail voltages. Desirably, first and second output isolating elements have inputs coupled to the first and second nodes, the output isolating elements being operable to output versions of the opposite rail-to-rail voltages as a true and a complementary output of the latch. In this way, the true output has a rising edge occurring simultaneously with a falling edge of the complementary output. The complementary output has a rising edge occurring simultaneously with a falling edge of the true output. First and second input isolating elements of the latch have outputs coupled to the first and second nodes, the first and second input isolating elements being operable to apply versions of input signals to the first and second nodes.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 30, 2009
    Inventors: Joseph Natonio, Steven J. Zier
  • Publication number: 20090102531
    Abstract: [Problems] To provide a semiconductor integrated circuit by which what has been referred to as two-pattern test is made possible without greatly increasing an occupying area. [Means for Solving Problems] the semiconductor integrated circuit is provided with a plurality of flip-flop circuits and selectors corresponding to each flip-flop circuit. Each flip-flop circuit is provided with a master latch and a slave latch connected to the master latch. The selector is electrically connected with the master latch of the flip-flop circuit to which the selector corresponds, and is also connected with the master latch of the flip-flop circuit other than the one to which the selector corresponds.
    Type: Application
    Filed: January 5, 2006
    Publication date: April 23, 2009
    Inventors: Kazutero Nanba, Hideo Ito
  • Patent number: 7514975
    Abstract: A circuit is disclosed for retaining a signal value during a sleep mode while a portion of said circuit is powered down comprising: a clock signal input operable to receive a clock signal; at least one latch clocked by said clock signal; a data input, a data output and a forward data path therebetween, wherein a signal value is operable to be received at said data input, is clocked through said at least one latch and passes to said data output along said forward data path; at least one of said at least one latch comprises a retention latch operable to retain a signal value during said sleep mode, said retention latch not being located on said forward data path; and a tristateable device, said tristateable device being arranged between said forward data path and said retention latch and being operable to selectively isolate said retention latch from said forward data path in response to receipt of a first sleep signal; wherein in response to receipt of a second sleep signal, said second sleep signal being rece
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: April 7, 2009
    Assignee: ARM Limited
    Inventors: Martin Frederick, Jr., James David Shiffer, III
  • Publication number: 20090085626
    Abstract: When a master circuit is in an inactive state, a slave circuit assigned to the master circuit is not used. Accordingly, the use efficiency of system recourses is decreased. To solve the above problem, a semiconductor integrated circuit reassigns a M2 region of a slave circuit, previously assigned to a first master circuit, to a second master circuit. That is to say, the M2 region of the slave circuit previously assigned to the first master circuit is reassigned to the second master circuit based on the operational status of the first master circuit. This improves the use efficiency of system resources of the semiconductor integrated circuit.
    Type: Application
    Filed: September 11, 2008
    Publication date: April 2, 2009
    Applicant: NEC ELECTRONICS CORPORATION
    Inventors: Shigeyuki Ueno, Hiroyuki Nakajima
  • 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