Clock Or Pulse Waveform Generating Patents (Class 327/291)
  • Patent number: 8279196
    Abstract: A display device using a surface capacitive touch panel is proposed. Upon a normal mode, an external clock generator supports a clock source; meanwhile, an external clock generator, a signal generator, a current detector, a current-to-voltage converter, an analog-to-digital converter, a filter, an interface controller, a microprocessor, and the touch-position calculators are turned on. But under a power-down mode, the external clock generator, the analog-to-digital converter, filter, the interface controller, the microprocessor, and the touch-position calculators are turned off in order to reduce power consumption. Furthermore, the external clock generator is also turned off to minimize the power consumption.
    Type: Grant
    Filed: June 24, 2009
    Date of Patent: October 2, 2012
    Assignee: Genesys Logic, Inc.
    Inventor: Mi-lai Tsai
  • Patent number: 8275064
    Abstract: A multiple-input-multiple-output (MIMO) wireless communication enhanced detection method and apparatus are proposed whereby quasi optimal link performance is achieved, at low complexity for MIMO systems including those of high dimension and those operating at very high SNR.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: September 25, 2012
    Assignee: Mint Access Fund, LLC
    Inventor: Daniel Nathan Nissani (Nissensohn)
  • Patent number: 8270557
    Abstract: An integrated circuit includes a counter configured to perform a counting operation and output a count code value. The integrated circuit further includes an operation controller, a digital circuit and an alignment unit. The operation controller receives the count code value and generates a first control signal and a second control signal. The first control signal is generated, when the count code value is equal to a first value, which is counted by the counter prior to a target count value. The second control signal is generated, when the count code value is equal to the target count value. A digital circuit performs a first operation based on the first control signal, and output a digital signal. An alignment unit aligns the digital signal, and outputs the aligned digital signal as a final digital signal in response to the second control signal.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: September 18, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventors: Ji-Wang Lee, Shin-Deok Kang
  • Patent number: 8269544
    Abstract: An integrated circuit that includes a digitally controlled oscillator (DCO) that adjusts a clock frequency of a critical path of the integrated circuit based on the variations in a power-supply voltage of the DCO and the critical path is described. This DCO may be included in a feedback control loop that includes a frequency-locked loop (FLL), and which determines an average clock frequency of the critical path based on a reference frequency. Furthermore, the DCO may have a selectable delay characteristic that specifies a delay sensitivity of the DCO as a function of the power-supply voltage, thereby approximately matching a manufactured delay characteristic of the critical path. Additionally, for variations in the power-supply voltage having frequencies greater than a resonance frequency associated with a chip package of the integrated circuit, adjustments of the clock frequency may be proportional to the variations in the power-supply voltage and the selectable delay characteristic.
    Type: Grant
    Filed: October 1, 2010
    Date of Patent: September 18, 2012
    Assignee: Oracle America, Inc.
    Inventors: David J. Greenhill, Robert P. Masleid, Georgios K. Konstadinidis, King C. Yen, Sebastian Turullols
  • Patent number: 8269525
    Abstract: A disclosed integrated circuit logic cell includes a clock input operative to receive a clock input from a clock tree of the integrated circuit, and clocking circuitry, internal to the logic cell, operative to place a plurality of clock nodes, within the logic cell, in a logical off state in response to a predetermined logic state of the logic cell, thereby preventing the clock nodes from toggling during the predetermined logic state of the logic cell. The integrated circuit logic cell includes primary logic circuitry, internal to the logic cell, operatively coupled to the clocking circuitry which is operatively coupled to an input of the primary logic circuitry. The clocking circuitry provides clock outputs operatively coupled to the clock nodes which are within the primary logic circuitry, and is operative to control the clock outputs in response to the predetermined logic state.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: September 18, 2012
    Assignee: ATI Technologies ULC
    Inventor: Omid Rowhani
  • Publication number: 20120229188
    Abstract: A semiconductor device including an internal terminal, a first transistor of a first conductivity type that is coupled between a first reference potential and the internal terminal, and that includes a first control terminal, a second transistor of a second conductivity type that is coupled between a second reference potential and the internal terminal, and that includes a second control terminal, an oscillator that includes an output terminal to output a clock signal, and a comparator that is coupled to the internal terminal, and that compares a potential of the internal terminal when the internal terminal is coupled to the first reference potential with a potential of the internal terminal when the internal terminal is coupled to the second reference potential. Each control terminals is coupled to the output terminal to commonly receive the clock signal, and the first and second transistors exclusively operate in response to the clock signal.
    Type: Application
    Filed: May 17, 2012
    Publication date: September 13, 2012
    Applicant: Renesas Electronics Corporation
    Inventor: Hiroyuki Kohamada
  • Patent number: 8264254
    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: April 21, 2009
    Date of Patent: September 11, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Mitsuaki Osame, Aya Anzai
  • Patent number: 8264267
    Abstract: A clock pulse generating circuit includes a pulse generator, a clock regulator, and a pre-driver. The pulse generator is configured to vary pulse widths of a rising clock signal and a falling clock signal. The clock regulator is configured to regulate output signals of the pulse generator to prevent an overlap and a duty drop of the output signals of the pulse generator. The pre-driver is configured to output data driving signals according to output signals of the clock regulator.
    Type: Grant
    Filed: December 29, 2009
    Date of Patent: September 11, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hun Sam Jung
  • Patent number: 8264266
    Abstract: A power-supply-independent clock, with controlled THigh and TLow that permits both frequency and duty cycle to be set simultaneously and independently. Depending upon the implementation, the control values can be varied for frequency and duty cycle as determined by the user, or can be dependent upon temperature, power supply variations, or any other variable within the system, design or device that includes the clock.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: September 11, 2012
    Assignee: Aivaka, Inc.
    Inventor: Ahmad B. Dowlatabadi
  • Patent number: 8258815
    Abstract: The present invention relates to a circuit for generating a clock signal. The circuit comprises a current source to generate a reference current and provide a first voltage V1, a first current generator to generate a first mirror current during a first half cycle based on the reference current, a first capacitor including a first end, and a first transistor having a first threshold voltage VTH1. The first transistor includes a gate to receive the first voltage V1, a drain coupled to the first current generator and a source coupled to the first end of the first capacitor so as to allow the first mirror current to charge the first capacitor during the first half cycle, wherein the period of the first half cycle is a function of the first bias voltage V1 minus the first threshold voltage VTH1.
    Type: Grant
    Filed: March 3, 2010
    Date of Patent: September 4, 2012
    Assignee: Macronix International Co., Ltd.
    Inventors: Chia Ching Li, Hsin Yi Ho, Chun Hsiung Hung
  • Patent number: 8258845
    Abstract: The relative timing of triggering switching events in a circuit block of an IC device is dynamically adjusted in response to fluctuations in device's supply voltage to minimize clock jitter caused by supply voltage noise. A control circuit monitors supply voltage fluctuations, and in response thereto dynamically phase-shifts a clock signal that triggers the switching events so that the switching events occur during relatively quiet time intervals in which fluctuations in the supply voltage are minimal.
    Type: Grant
    Filed: May 20, 2005
    Date of Patent: September 4, 2012
    Assignee: Xilinx, Inc.
    Inventors: Mark A. Alexander, Sean A. Koontz
  • Patent number: 8253469
    Abstract: It is an object of the present invention to provide a semiconductor device that has a simple circuit structure, a small scale, and low power consumption, and can generate a desired clock signal. The semiconductor device has a clock generation circuit which generates a clock signal by dividing a modulated carrier wave, a divider circuit which generates a first divided signal by dividing a carrier wave, and a correction circuit which generates a second divided signal by further dividing the first divided signal, and has a function of performing correction for inverting the second divided signal in a period corresponding to a half period of the clock signal during modulation of the carrier wave and selecting whether the correction is performed or not.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: August 28, 2012
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Tomoaki Atsumi
  • Patent number: 8253468
    Abstract: According to one embodiment, a clock generating circuit includes first and second current generating circuits, first and second voltage generating circuits, first and second comparing circuits, a clock output circuit, a control circuit. The first current generating circuit is configured to generate a first current. The first voltage generating circuit is configured to generate a first voltage which increases or decreases according to a phase of a clock signal as time advances by the first current. The first comparing circuit is configured to compare the first voltage with a first threshold voltage to generate a first comparison result. The second current generating circuit is configured to generate a second current. The second comparing circuit is configured to compare the second voltage with a second threshold voltage to generate a second comparison result.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: August 28, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Chikashi Nakagawara
  • Publication number: 20120212276
    Abstract: A power converter operable to draw an input current that is in phase with an input voltage of the power converter and proportional to a voltage of the input voltage of the power converter includes a drive switch, a waveform generator, and a current shaping circuit. The drive switch is connected between an input inductor and ground and draws current through the input inductor when turned on. The current shaping circuit provides an on-time of the drive switch for a next cycle of the drive switch as a function of an input current decay time, a switching period of the waveform generator, and an output voltage of the power converter. The waveform generator is responsive to the on-time provided by the current shaping circuit for selectively turning the drive switch on and off to cycle the drive switch as a function of the received on-time.
    Type: Application
    Filed: February 10, 2012
    Publication date: August 23, 2012
    Inventors: Silvio Ziegler, Ivan Feno
  • Patent number: 8248139
    Abstract: An apparatus for interleaved phase shift clock synchronization includes a master clock generator and at least one slave clock generator. The master clock generator provides a ramp signal or reset signal for each slave clock generator to generate a clock synchronized with the clock of the master clock generator, and the master and slave clock generators have different reference voltages for generating clocks. Therefore, the clocks generated will be synchronized and interleaved phase with each other.
    Type: Grant
    Filed: December 23, 2010
    Date of Patent: August 21, 2012
    Assignee: Richtek Technology Corp.
    Inventors: Isaac Y. Chen, An-Tung Chen
  • Patent number: 8248137
    Abstract: An apparatus for processing signals, in particular physiological measuring signals, wherein the apparatus is provided with different channels with signal inputs (1) for receiving input signals, which input signals each comprise a specific signal component and a signal component common to all input signals, wherein each channel is provided with an impedance transforming input amplifier (3), wherein the apparatus is configured for supplying to the non-inverting input of each input amplifier (3) a respective input signal and, to the inverting input an analogue reference signal common to all channels, wherein the apparatus is provided with a digital signal processor (10) and one more or analogue-digital converters (5) for supplying the signals provided by the input amplifiers (3) to the digital signal processor (10), wherein the signal processor (10) is designed for converting the signals received from the one or more analogue digital converters (5) into one or more output signals.
    Type: Grant
    Filed: August 4, 2008
    Date of Patent: August 21, 2012
    Assignee: Twente Medical Systems International B.V.
    Inventor: Jan Hendrik Peuscher
  • Patent number: 8248125
    Abstract: A multi-port circuit and corresponding method for simultaneous shaping of sub-nanosecond pulses (MCS3P). The MCS3P includes a coupled-line coupler, a Schottky detector diode, and circuitry for compressing the rising and falling edges of a waveform. The MCS3P simultaneously produces square wave, Gaussian, and monocycle waveforms by differentiating a sinusoidal source. The method includes the steps of compressing the rising edge of a sinusoidal source waveform, differentiating the resulting waveform to form a square waveform and a Gaussian waveform, filtering out the positive going Gaussian to produce a negative going Gaussian, differentiating the Gaussian waveform to form a monocycle waveform, and compressing the falling edge of the square waveform to produce a square wave form with both edges compressed.
    Type: Grant
    Filed: February 9, 2012
    Date of Patent: August 21, 2012
    Assignee: University of South Florida
    Inventors: Erick Maxwell, Thomas Weller, Ebenezer Odu
  • Patent number: 8248138
    Abstract: The present invention relates to a method and an apparatus, during a phase switching process, for choosing all of outputted phases upon the clock phases devoid of phase switching so as to avoid glitches during clock switching. Compared with the conventional approach for removing glitches by controlling a clock switching sequence, an improvement of a phase rotator is further disclosed in the present invention, which eliminates the glitches of the outputted phase clock so as to realize a glitch-less phase switching in a phase interpolation circuit.
    Type: Grant
    Filed: March 9, 2010
    Date of Patent: August 21, 2012
    Assignee: Realtek Semiconductor Corp.
    Inventor: Ye Liu
  • Publication number: 20120206183
    Abstract: An electronic device comprises a first component susceptible to a wearout effect, operation of which first component depends on an operating parameter, and a second component having an on-state and an off-state. The electronic device further comprises a time estimator for updating an estimate of an accumulated time the second component was in the on-state; and a controller for controlling the operating parameter on the basis of the accumulated time estimate so as to respond to the expected wearout effect. The first component and the second component may be the same, or the first component may have an on-state correlated to the on-state of the second component. The operating parameter may, for example, be a level or amplitude or correction value of one of the following: a voltage applied at the first component, an electric current fed to the first component, and a power provided to the first component. A method of operating such an electronic device is also disclosed.
    Type: Application
    Filed: November 6, 2009
    Publication date: August 16, 2012
    Applicant: Freescale Semiconductor, Inc.
    Inventors: Michael Priel, Anton Rozen, Yossi Shoshany
  • Patent number: 8242829
    Abstract: Methods, systems, and apparatus can provide a multichannel interpolator while optimizing circuitry reuse.
    Type: Grant
    Filed: June 24, 2010
    Date of Patent: August 14, 2012
    Assignee: ARRIS Group, Inc.
    Inventor: Oleksandr Volkov
  • Patent number: 8237481
    Abstract: A programmable Local Clock Buffer has a single inverter between the clock input and the delayed clock output. A transistor switch modulates the single inverter stage between a clock signal transmit state and a non-transmitting state. A combination of delay select bits control the timing of the beginning and ending of the transmit state of the inverter relative to the clock input via the transistor switch.
    Type: Grant
    Filed: April 25, 2008
    Date of Patent: August 7, 2012
    Assignee: International Business Machines Corporation
    Inventors: Yuen H. Chan, Rolf Sautter, Michael J. Lee, Juergen Pille
  • Patent number: 8237484
    Abstract: A circuit includes a clock generator to provide a clock signal, and a clock distribution circuit coupled to the clock generator and a plurality of pairs of outputs. The clock distribution circuit includes a plurality of adjustment circuits to generate a plurality of pairs of clock signals in accordance with the clock signal. A respective adjustment circuit in the plurality of adjustment circuits is to provide a respective pair of clock signals in the plurality of pairs of clock signals to a respective pair of outputs in the plurality of pairs of outputs. The respective pair of clock signals includes a first clock signal and a second clock signal. The first clock signal is a complement of the second clock signal and duty-cycle and skew errors in the first clock signal and the second clock signal are less than corresponding pre-determined values.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: August 7, 2012
    Assignee: Rambus Inc.
    Inventors: Kambiz Kaviani, Tsu-Ju Chin
  • Patent number: 8237482
    Abstract: A circuit comprises a frequency divider coupled to receive an oscillating signal generated by an oscillator and a division ratio and configured to divide the oscillating signal by the division ratio into a clock signal; a temperature compensation circuit configured to measure a temperature of the oscillator and generate a division ratio to be provided to the frequency divider and a first value on the basis of the measured temperature; and a control system configured to control connection between a calibration element and the oscillator based on the first value and the oscillating signal of the oscillator.
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: August 7, 2012
    Assignee: STMicroelectronics (Shenzen) R&D Co. Ltd.
    Inventor: Henry Ge
  • Patent number: 8237483
    Abstract: A circuit for processing a clock signal including first and second clock edges of different polarities, the circuit including an inverter for inverting a first clock edge to generate an inverted first clock edge and inverting a second clock edge to generate an inverted second clock edge; a first pass gate for receiving the inverted clock edge and outputting a first trigger signal of a first polarity; and a second pass gate for receiving the second clock edge and outputting a second trigger signal of the first polarity, wherein the second pass gate is controlled to open responsive to the inverted second clock edge; whereby the delay between the first clock edge and the first trigger signal is substantially equal to the delay between the second clock edge and second trigger signal.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: August 7, 2012
    Assignee: STMicroelectronics International N.V.
    Inventors: Nitin Gupta, Nitin Jain
  • Patent number: 8238508
    Abstract: A device for extracting a clock signal from a baseband serial signal, includes an injection-locked oscillator (19), a phase-locked loop (25) including a digital phase detector (26). The oscillator (19) includes a digital input for controlling the value of its natural frequency, and the phase-locked loop (25) includes a counting circuit (30, 35) aggregating the relative values of the digital signal supplied by the digital phase detector (26) and supplying a control signal in digital form for the oscillator (19).
    Type: Grant
    Filed: April 4, 2008
    Date of Patent: August 7, 2012
    Assignee: Centre National d'Etudes Spatiales (C.N.E.S.)
    Inventors: Michel Pignol, Claude Neveu, Yann Deval, Jean-Baptiste Begueret, Olivier Mazouffre
  • Publication number: 20120194230
    Abstract: A control circuit 10 includes an internal clock generating portion (12), which starts generating an internal clock signal (LCLK) required by a control portion (11) to perform action when a specific signal pattern appears in a trigger signal, continually generates the internal clock signal (LCLK) at least before the control portion (11) completes predetermined processing, and then stops generating the internal clock signal (LCLK); and the control portion (11), which uses the internal clock signal (LCLK) to perform the predetermined processing.
    Type: Application
    Filed: December 21, 2011
    Publication date: August 2, 2012
    Applicant: ROHM CO., LTD.
    Inventors: Hiromitsu Kimura, Yoshinobu Ichida
  • Publication number: 20120175247
    Abstract: A pulse generator includes a wave generator connected to a power source, the wave generator having an output signal; a de-multiplexer having a single input for receiving the output signal of the wave generator and splitting the signal into a plurality of channels carrying corresponding DeMux output signals; and a multiplexer electrically connected to each of the DeMux output signals and including means for alternately advancing or retarding the time interval between pulses of each the DeMux output signals and for combining at least two of the advanced or retarded output signals together and outputting the at least two advanced or retarded output signals as a single circuit output signal having a diverse pulse train. Pulse control means for controlling at least one of the pulse width and pulse amplitude of the circuit output signal is also provided.
    Type: Application
    Filed: January 9, 2012
    Publication date: July 12, 2012
    Inventor: Fletcher Darrel
  • Patent number: 8217698
    Abstract: The clock circuit of an integrated circuit operates with variations such as temperature, ground noise, and power noise. Various aspects of an improved clock integrated circuit address one or more of the variations in temperature, ground noise, and power noise.
    Type: Grant
    Filed: May 6, 2011
    Date of Patent: July 10, 2012
    Assignee: Macronix International Co., Ltd.
    Inventors: Chung-Kuang Chen, Chun-Hsiung Hung, Han-Sung Chen
  • Patent number: 8217697
    Abstract: A clock generation circuit, includes, in part, a comparator, a logic unit, and a switching circuit. The switching circuit generates a signal that is applied to the comparator. If the input voltage level of the signal applied to the comparator is greater than a first reference voltage, the comparator asserts its first output signals. If the input voltage level of the signal applied to the comparator is less than a second reference voltage, the comparator asserts its second output signal. The output signals of the comparator form a first pair of feedback signals applied to the switching circuit. The logic unit responds to the output signals of the comparator to generate a second pair of oscillating feedback signals that are also applied to the switching circuit. The switching circuit varies a capacitor voltage in response to a reference current and in response to the two pairs of feedback signals it receives.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: July 10, 2012
    Assignee: Intersil Americas Inc.
    Inventor: Harold William Satterfield
  • Publication number: 20120169394
    Abstract: A method buffers clock skew by using a logical effort, and is applicable to a clock tree that stays in a strong-inversion region, a moderate-inversion region, or a weak-inversion region. The method includes establishing in the clock tree a temperature sensor and a tunable-width buffer, and establishing width and temperature comparative lists according to a logical effort equation, for the tunable-width buffer to be individually applied to the strong-inversion region, the moderate-inversion region, and the weak-inversion region; selecting one from the width and temperature comparative lists that corresponds to one of the inversion regions in which the clock tree stays, enabling the temperature sensor to sense a temperature, and searching the selected width and temperature comparative list for a width that corresponds to the temperature sensed by the temperature sensor; and enabling the tunable-width buffer to perform a width modulation process according to the searched width.
    Type: Application
    Filed: June 8, 2011
    Publication date: July 5, 2012
    Applicant: NATIONAL CHIAO TUNG UNIVERSITY
    Inventors: Chung-Ying Hsieh, Ming-Hung Chang, Wei Hwang
  • Patent number: 8212601
    Abstract: A method and apparatus for providing system clock failover using a one-shot circuit are disclosed. A process, in one embodiment, is able to detect a clock failure using a one-shot circuit, wherein the clock signals are generated by a first clock circuit. Upon generating a switching signal in response to the clock failure, a system reset signal is asserted for a predefined time period in accordance with the clock failure. After switching a second clock circuit to replace the first clock circuit, the process is capable of resuming the clock signals via the second clock circuit.
    Type: Grant
    Filed: October 29, 2010
    Date of Patent: July 3, 2012
    Assignee: Netgear, Inc.
    Inventor: Eric Roger Davis
  • Patent number: 8193847
    Abstract: A timing circuit and corresponding method are provided to generate an output timing signal in dependence on an input timing signal. The timing circuit comprises a plurality of circuit components, each circuit component configured to receive an input dependent on the input timing signal and to generate an output in dependence on that input. Each circuit component performs switching operations by switching its output level in response to a transition of its input level. Each circuit component exhibits a delay in switching its output level, the delay comprising a first delay associated with a first switching of its output level and a second delay associated with a second switching of its output level. The first switching is in an opposite direction to the second switching and the first delay and the second delay exhibit a change in magnitude as each circuit component repeatedly performs its switching operations.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: June 5, 2012
    Assignee: ARM Limited
    Inventors: Sebastien Nicolas Ricavy, Nicolaas Klarinus Johannes van Winkelhoff, Gerald Jean Louis Gouya
  • Publication number: 20120126871
    Abstract: A method and apparatus of alternating service modes of a silicon on insulator (SOI) process circuit includes determining whether the SOI process circuit is in a first or second service mode. A first clock or a second clock is selected for transmission along a buswire of the SOI process circuit based upon the determination. A receiving device of the signal is notified whether the SOI process circuit is operating in the first service mode or the second service mode.
    Type: Application
    Filed: November 24, 2010
    Publication date: May 24, 2012
    Applicant: ADVANCED MICRO DEVICES, INC.
    Inventors: Joseph E. Kidd, Brian W. Amick, Ryan J. Hensley, James R. Magro, Ronald L. Pettyjohn
  • Publication number: 20120127811
    Abstract: According to an embodiment, a semiconductor storage device includes a memory cell array, a plurality of sense amplifiers and a timing generation circuit. The memory cell array includes a plurality of word lines, a plurality of bit lines crossing the plurality of word lines, and a plurality of memory cells provided in intersection portions of the plurality of word lines and the plurality of bit lines. The plurality of sense amplifiers is configured to detect a signal level of the corresponding bit lines. The timing generation circuit includes a timing selection circuit configured to select a timing in a preset order from among timings in which each bit line signal in the plurality of bit lines changes. The timing generation circuit is configured to generate activation timing to activate the plurality of sense amplifiers based on the selected timing.
    Type: Application
    Filed: March 22, 2011
    Publication date: May 24, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Atsushi Kawasumi
  • Patent number: 8183905
    Abstract: A method to provide a low-power clock signal or a low-noise clock signal is described herein. It is determined whether a low-power mode or a low-noise mode is in use. A voltage reference input of a low-dropout voltage regulator (LDO) is switched to a low-power voltage reference for low-power mode and to a low-noise voltage reference for low-noise mode. The LDO provides a constant voltage output to a crystal oscillator. A clock signal is generated using the crystal oscillator. The clock signal is limited using a low-power limiter to generate a low-power output clock signal and/or is limited using a low-noise limiter to generate a low-noise clock signal. The low-power output clock signal or the low-noise output clock signal is selected using a mux.
    Type: Grant
    Filed: August 11, 2009
    Date of Patent: May 22, 2012
    Assignee: Broadcom Corporation
    Inventors: Yuyu Chang, Qiang Li, John Leete, Hooman Darabi, Yiannis Kokolakis
  • Patent number: 8181058
    Abstract: A receiver circuit is described. In the receiver circuit, an analog-to-digital converter (ADC) generates first samples of a data signal based on a first clock signal, and a clock-data-recovery (CDR) error-detection circuit generates second samples of the data signal based on a second clock signal. In addition, the CDR error-detection circuit estimates intersymbol interference (ISI) at a current sample in the second samples from an adjacent, subsequent sample in the second samples. Based on the second samples and the estimated ISI, a CDR circuit generates the first clock signal and the second clock signal, which involves modifying the skews of either or both of these clock signals so that the current sample is associated with a zero crossing of a pulse response of a communication channel from which the data signal was received, thereby reducing or eliminating the ISI from the adjacent, subsequent sample.
    Type: Grant
    Filed: January 6, 2010
    Date of Patent: May 15, 2012
    Assignee: Oracle America, Inc.
    Inventors: Jianghui Su, Deqiang Song, Dawei Huang, Muthukumar Vairavan
  • Patent number: 8179182
    Abstract: Methods and apparatuses provide a clocked digital device having dynamically adjustable operating characteristics. The digital device comprises a digital clock management (“DCM”) circuit in which the amount of delay between receipt of an active edge of a clock signal at the input of the DCM circuit and appearance of an active edge of another clock signal at the output of the DCM circuit depends on a phase adjustment signal applied to the DCM circuit's phase adjust input. A phase adjustment circuit provides the phase adjustment signal to the DCM circuit's phase adjust input for controlling the amount of the delay between the clock signal at the input of the DCM circuit and the clock signal at the output of the DCM circuit.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: May 15, 2012
    Assignee: Texas Memory Systems, Inc.
    Inventor: Charles J. Camp
  • Patent number: 8179181
    Abstract: A power-mode-aware (PMA) clock tree and a synthesis method thereof are provided. The clock tree includes a sub clock tree and a PMA buffer. The sub clock tree transmits a delayed clock signal to a function module, wherein a power mode of the function module is determined according to a power information. The PMA buffer is coupled to the sub clock tree. The PMA buffer determines the delay time of a system clock signal according to the power information delays the system clock signal, and outputs the delayed system clock signal to the sub clock tree as the delayed clock signal.
    Type: Grant
    Filed: March 31, 2010
    Date of Patent: May 15, 2012
    Assignees: Industrial Technology Research Institute, National Tsing Hua University
    Inventors: Chiao-Ling Lung, Shih-Chieh Chang
  • Patent number: 8174302
    Abstract: A pulse signal generator includes a period setting unit that receives a period set signal including an information indicative of a pulse period, and that outputs a period control signal controlling the pulse period, a duty ratio setting unit that receives a duty ratio set signal including an information indicative of a duty ratio of a pulse, that receives a signal including the pulse period set in the period setting unit, and that generates a duty ratio control signal controlling the duty ratio of the pulse on a basis of the pulse period and the duty ratio set signal, and a pulse generation unit that generates a pulse signal including the pulse period and the duty ratio of the pulse on a basis of the period control signal and the duty ratio control signal.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: May 8, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Yasuyuki Fujiwara
  • Patent number: 8174301
    Abstract: Phase-error-reduction circuitry for an IQ generator, wherein the phase-error-reduction circuitry is arranged to receive I and Q input signals from the IQ generator and to produce I and Q output signals, and wherein the phase-error-reduction circuitry is arranged to sample the I and Q input signals to tend to reduce a phase error between the I and Q output signals.
    Type: Grant
    Filed: November 12, 2008
    Date of Patent: May 8, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Robert Braun, Bardo Muller
  • Patent number: 8170157
    Abstract: The communication system having a transmitter and a receiver, wherein the transmitter and the receiver are coupled by a clock channel and a data channel, wherein the clock channel is shorter than the data channel and wherein the receiver comprises a delay circuit for extracting a jitter signal from a clock channel signal, delaying the extracted jitter signal, and generating a receiver clock signal for the receiver by the delayed jitter signal.
    Type: Grant
    Filed: December 20, 2007
    Date of Patent: May 1, 2012
    Assignee: International Business Machines Corporation
    Inventors: Christian I. Menolfi, Martin Leo Schmatz, Thomas H. Toifl
  • Patent number: 8169225
    Abstract: High Speed I/O interfaces such as DVI, S-ATA or PCI-Express require expensive test equipment. Loop-back tests are widely used as one alternative, but lack coverage of timing-related defects. A system and method for on-chip jitter injection using a variable delay with controllable amplitude and high accuracy is provided that improves the coverage of loop-back tests.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: May 1, 2012
    Assignee: NXP B.V.
    Inventor: Rodger Frank Schuttert
  • Patent number: 8166357
    Abstract: A method and apparatus for implementing integrated circuit security features are provided to selectively disable testability features on an integrated circuit chip. A test disable logic circuit receives a test enable signal and responsive to the test enable signal set for a test mode, establishes a test mode and disables ASIC signals. Responsive to the test enable signal not being set, the ASIC signals are enabled for a functional mode and the testability features on the integrated circuit chip are disabled. When the functional mode is enabled, the test disable logic circuit prevents the test mode from being established while the integrated circuit chip is powered up.
    Type: Grant
    Filed: December 26, 2007
    Date of Patent: April 24, 2012
    Assignee: International Business Machines Corporation
    Inventors: David Warren Pruden, Dennis Martin Rickert, Brian Andrew Schuelke
  • Patent number: 8164392
    Abstract: An isolation switch is used to isolate the output of an oscillator, during startup of the oscillator, from the circuitry that uses the periodic signal generated by the oscillator. In one implementation, a device may include an oscillator to generate a periodic signal and a switch connected to receive an output of the oscillator. The switch may include a control input that controls whether the switch is in an open or closed state. Switch control circuit may control the switch so that the switch is in an open state during startup of the oscillator and the switch is in a closed state thereafter.
    Type: Grant
    Filed: April 26, 2010
    Date of Patent: April 24, 2012
    Assignee: Juniper Networks, Inc.
    Inventors: David P. Chengson, Victor Do
  • Patent number: 8164390
    Abstract: An integrated circuit has operational circuitry to perform an operation. An operational regulator regulates an operating condition of the operational circuitry. The operational regulator has a sample clock to generate a sample clock signal. The sample clock signal correlates to a manufacturing variation of the electronic circuitry. The operational regulator also includes a configurator to evaluate the sample clock signal and generate a configuration signal according to the evaluation. A controller is provided to receive the configuration signal and control an operating condition of the operational circuitry according to the configuration signal.
    Type: Grant
    Filed: March 14, 2008
    Date of Patent: April 24, 2012
    Assignees: Marvell International Ltd., Marvell Israel (MISL) Ltd.
    Inventors: Randall D. Briggs, Eran Maor, Walter Lee McNall, William B. Weiser, Haggai Telem
  • Patent number: 8164375
    Abstract: A synchronizer system and method that can be used with a conventional adjustable delay circuit to preserve a pseudo-synchronous phase relationship between clock signals of different clock domains when the time delay of the adjustable delay circuit from which one of the clock signals is output is changed.
    Type: Grant
    Filed: September 28, 2009
    Date of Patent: April 24, 2012
    Assignee: Round Rock Research, LLC
    Inventor: Paul A. LaBerge
  • Patent number: 8164374
    Abstract: Provided is a clock gating circuit which receives a first clock signal and controls an output of a second clock signal corresponding to the first clock signal in response to a control signal. The clock gating circuit includes: a first latch that latches a signal value of the control signal in synchronization with the first clock signal; an AND that receives the first clock signal and controls an output of the second clock signal in response to an output signal of the first latch; and a second latch that latches a signal value of the output signal of the first latch in synchronization with the first clock signal, and outputs a latched value. This enables execution of a scan test with a simple circuit configuration.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: April 24, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Kazuyuki Irie
  • Publication number: 20120086490
    Abstract: An integrated circuit device includes an external power supply input configured to be coupled to an external power supply and a digital circuit, such as a clock signal generator circuit, that generates noise at a power supply input thereof. The device further includes a replica load circuit and a power supply circuit coupled to the external power supply input, to a power supply input of the digital circuit and to a power supply input of the replica load circuit. The power supply circuit is configured to selectively couple the external power supply node to the power supply input of the digital circuit responsive to a voltage at the power supply input of the replica load circuit. The replica load circuit may be configured to provide a load that varies responsive to a voltage at the power supply input of the digital circuit.
    Type: Application
    Filed: September 22, 2011
    Publication date: April 12, 2012
    Inventors: Su-yeon Doo, Seung-jun Bae, Kwang-il Park, Young-soo Sohn
  • Publication number: 20120081585
    Abstract: There is provided a drive circuit of a solid-state image pickup device capable of generating pulse for vertical scanning the interval of which changes non-linearly and pulse other than the pulse for vertical scanning without increasing a circuit size and communication time for setting an electronic shutter. There is provided a drive circuit of a solid-state image pickup device including a polynomial arithmetic operation unit for carrying out an arithmetic operation of first or higher order of polynomial; an arithmetic operation controller of generating a variable of the polynomial to control an arithmetic operation in the polynomial arithmetic operation unit; and a pulse generator of generating a pulse based on a result of an arithmetic operation on a polynomial of the polynomial arithmetic operation unit.
    Type: Application
    Filed: December 12, 2011
    Publication date: April 5, 2012
    Applicant: Canon Kabushiki Kaisha
    Inventor: Shintaro Takenaka
  • Patent number: 8149039
    Abstract: A picosecond pulse generator apparatus and methodology is disclosed. A pulse generator is provided by forming a transmission line and a switching element on a common semiconductor substrate or semiconductor chip. The transmission line and the switching element can be provided on the common CMOS semiconductor substrate using standard CMOS technology. A voltage is applied to the transmission line to charge the transmission line. An input pulse is applied to the switching device to trigger the switching device to cause the transmission line to discharge an output pulse across a load resistor. The pulse width of the output pulse depends in major part on the length of the transmission line. Additional components can be provided on the common semiconductor substrate or chip to shape the input pulse to the switching device to ensure a fast rise time.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: April 3, 2012
    Assignee: Clemson University
    Inventors: Pingshan Wang, Chaojiang Li