Single Clock Output With Single Clock Input Or Data Input Patents (Class 327/299)
  • Publication number: 20100097071
    Abstract: An integrated circuit capable of on-chip jitter tolerance measurement includes a jitter generator circuit to produce a controlled amount of jitter that is injected into at least one clock signal, and a receive circuit to sample an input signal according to the at least one clock signal. The sampled data values output from the receiver are used to evaluate the integrated circuit's jitter tolerance.
    Type: Application
    Filed: March 19, 2008
    Publication date: April 22, 2010
    Applicant: RAMBUS INC.
    Inventors: Hae-Chang Lee, Jaeha Kim, Brian Leibowitz
  • Patent number: 7683691
    Abstract: Disclosed herein is a clock supplying apparatus for supplying a clock to a digital circuit, including: a differential clock driver; a first clock line along which a first clock of a positive phase from the clock driver propagates; a second clock line along which a second clock of a reverse phase from the clock driver propagates; and a parallel resonance circuit of an inductor and a capacitor. The inductor of the parallel resonance circuit is connected at a first end to the first clock line and at a second end to the second clock line. The capacitor of the parallel resonance circuit is connected at a first electrode to the first clock line and at a second electrode to the second clock line.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: March 23, 2010
    Assignee: Sony Corporation
    Inventor: Ichiro Kumata
  • Patent number: 7683692
    Abstract: Clock control is handed over in a bus circuit from a first circuit (14) to a second circuit (12). A clock conductor (10a) is driven to a predetermined voltage level with the driver circuit of the first circuit after a last clock period following the start of execution of the handover command and to continue driving the clock conductor (10a) to the predetermined voltage level for a first time-interval. The clock conductor (10a) is driven to the predetermined voltage level with the driver circuit of the second circuit after a second time interval following the start of execution of the handover command until a third time interval has elapsed following the end of the second time interval. Subsequently the clock conductor (10a) is driven under control of the clock circuit (140) of the second circuit (14).
    Type: Grant
    Filed: September 21, 2006
    Date of Patent: March 23, 2010
    Assignee: ST-Ericsson SA
    Inventors: Xavier Lambrecht, Bernardus Adrianus Cornelis Van Vlimmeren
  • Publication number: 20100060335
    Abstract: A clock synchronization system and method avoids output clock jitter at high frequencies and also achieves a smooth phase transition at the boundary of the coarse and fine delays. The system may use a single coarse delay line configured to generate two intermediate clocks from the input reference clock and having a fixed phase difference therebetween. The coarse delay line may have a hierarchical or a non-hierarchical structure. A phase mixer receives these two intermediate clocks and generates the final output clock having a phase between the phases of the intermediate clocks. The coarse shifting in the delay line at high clock frequencies does not affect the phase relationship between the intermediate clocks fed into the phase mixer. The output clock from the phase mixer is time synchronized with the input reference clock and does not exhibit any jitter or noise even at high clock frequency inputs. Because of the rules governing abstracts, this abstract should not be used to construe the claims.
    Type: Application
    Filed: November 17, 2009
    Publication date: March 11, 2010
    Inventors: Jongtae Kwak, Kang Yong Kim
  • Patent number: 7675341
    Abstract: A method and device for generating a clock signal, the method including measuring, using a first clock signal, a characteristic of a reference event in a received signal, determining, using the first clock signal, a variation of a characteristic of a second event in a received signal, correcting the measurement according to the variation of the characteristic of the second event, and generating a second clock signal using the first clock signal according to the corrected measurement.
    Type: Grant
    Filed: March 3, 2008
    Date of Patent: March 9, 2010
    Assignee: STMicroelectronics SA
    Inventors: Christophe Moreaux, Ahmed Kari, David Naura, Pierre Rizzo
  • Publication number: 20100045355
    Abstract: In a semiconductor device capable of radio communication, a stable clock signal is generated even if a reference clock signal for generating a clock signal has varied frequencies in each cycle. A clock signal generation circuit includes an edge detection circuit that detects an edge of an input signal and generates a synchronization signal, a reference clock signal generation circuit that generates a clock signal which functions as reference, a counter circuit that counts the number of edges of rise of the reference clock signal in accordance with the synchronization signal, a duty ratio selection circuit that selects a duty ratio of a clock signal from a count value, and a frequency division circuit that generates the clock signal having the selected duty ratio.
    Type: Application
    Filed: October 30, 2009
    Publication date: February 25, 2010
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventor: Masami Endo
  • Patent number: 7659763
    Abstract: A conditioning buffer is provided for a clock interpolator that controls the duration of the clock edges to achieve high-linearity interpolation. The conditioning buffer includes a first buffer and a second buffer, with a fixed or variable strength, that receive their respective inputs from a set of mutually delayed clock signals, such as a set of N equidistant clock phases with mutual delay of 360/N degrees, to form a two-tap transversal filter that is insensitive to changes in Process, Temperature, and Voltage (PVT). Use of an equidistant set of clock phases makes the time constant of such transversal filter proportional to the clock period thus making it insensitive to changes in clock frequency as well. Such transversal filtering action operated in conjunction with natural bandwidth limitations of the buffers yields an efficient clock conditioning circuit that is highly insensitive to PVT and clock frequency variations.
    Type: Grant
    Filed: March 4, 2008
    Date of Patent: February 9, 2010
    Assignee: International Business Machines Corporation
    Inventors: Hibourahima Camara, Sergey V. Rylov
  • Patent number: 7652516
    Abstract: A apparatus and method are disclosed for generating one or more clock signals. A clock signal is generated based on pattern signals and a reference clock signal. When the reference clock signal transitions high, the state of a first pattern signal is output, and when the reference clock signal transitions low, the state of a second pattern signal is output. Successive states of the first and second pattern signals, selected according to the reference clock signal, provide the generated clock signal.
    Type: Grant
    Filed: October 22, 2007
    Date of Patent: January 26, 2010
    Assignee: Marvell Israel (M.I.S.L.) Ltd.
    Inventors: Ido Bourstein, Yiftach Banai, Gil Stoler
  • Patent number: 7642874
    Abstract: An oscillator circuit may be used with controller circuits that are designed to operate with crystals, with no modifications to the pinout or firmware of the controller circuit. In some embodiments, the oscillator circuit includes an enable input that is responsive to low-amplitude transitions, which may be coupled to and driven by the crystal output signal of the controller circuit. When transitions are present on the crystal output signal, the oscillator circuit enables its clock output signal. When the controller circuit disables its crystal output signal, the oscillator circuit no longer detects transitions on the crystal output signal coupled to the oscillator circuit enable input, and disables the clock output signal.
    Type: Grant
    Filed: March 31, 2007
    Date of Patent: January 5, 2010
    Assignee: SanDisk Corporation
    Inventor: Steven T. Sprouse
  • Patent number: 7642873
    Abstract: An oscillator circuit may be used with controller circuits that are designed to operate with crystals, with no modifications to the pinout or firmware of the controller circuit. In some embodiments, the oscillator circuit includes an enable input that is responsive to low-amplitude transitions, which may be coupled to and driven by the crystal output signal of the controller circuit. When transitions are present on the crystal output signal, the oscillator circuit enables its clock output signal. When the controller circuit disables its crystal output signal, the oscillator circuit no longer detects transitions on the crystal output signal coupled to the oscillator circuit enable input, and disables the clock output signal.
    Type: Grant
    Filed: March 31, 2007
    Date of Patent: January 5, 2010
    Assignee: SanDisk Corporation
    Inventor: Steven T. Sprouse
  • Publication number: 20090327791
    Abstract: A method of providing a clock frequency to a processor is described. The method in accordance with the invention comprises the step of providing at least one reference signal and the step of determining a control value which relates to a desired first frequency. A second signal that relates to the control value is then used in a subsequent step as an input signal for a noise shaper. Then, a first signal which has the first frequency is generated by combining the output of the noise shaper with one of the at least one reference signals. The first signal is used as a clock frequency of the processor. In a preferred embodiment, one reference signal with a fixed reference frequency is provided. The reference signal is gated or enabled and hold by the output signal provided by a 1-bit noise shaper, whereby the first frequency is generated which is then used as processor clock frequency.
    Type: Application
    Filed: June 6, 2007
    Publication date: December 31, 2009
    Applicant: NXP B.V.
    Inventor: Steven Aerts
  • Publication number: 20090322400
    Abstract: An integrated circuit with a non-crystal reference clock includes: an oscillator adapted to generate and transmit an oscillator output signal, wherein the oscillator includes at least one of an inductor, a resistor, and a capacitor; a comparator adapted to receive the oscillator output signal and a calibration input signal, compare the oscillator output signal characteristics and the calibration input signal characteristics, and generate and transmit a first comparator signal in response to the comparison of the oscillator output signal and the calibration input signal, a state machine adapted to receive the first comparator signal, analyze the first comparator signal and calibrate the oscillator in response to the analysis of the first comparator signal, and a controller adapted to the receive the oscillator output signal, wherein a frequency of the oscillator output signal is utilized by the controller as a clock frequency.
    Type: Application
    Filed: June 27, 2008
    Publication date: December 31, 2009
    Inventor: Yao H. Kuo
  • Patent number: 7639058
    Abstract: The semiconductor device is provided with a clock signal generation circuit that includes a reference clock signal generation circuit which generates a first reference clock signal, a first counter circuit which counts the number of rising edges of the first reference clock signal by using the first reference clock signal and a synchronizing signal, a second counter circuit which counts the number of rising edges of the first reference clock signal by using an enumerated value of the first counter circuit, a first divider circuit which divides a frequency of the first reference clock signal by using the enumerated value of the first counter circuit and generates a second reference clock signal, and a second divider circuit which divides a frequency of the second reference clock signal and generates a clock signal.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: December 29, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Yoshiyuki Kurokawa, Takayuki Ikeda, Masami Endo, Hiroki Dembo, Daisuke Kawae, Takayuki Inoue, Munehiro Kozuma
  • Patent number: 7629826
    Abstract: Disclosed is a circuit for generating pulses for a semiconductor apparatus. The circuit for generating pulses for a semiconductor apparatus includes a temperature sensor, a temperature signal decoder, and a pulse generator. The temperature sensor senses the temperature of a memory chip and converts the temperature into a digital code combination so as to output a plurality of temperature information signals. The temperature signal decoder decodes the plurality of temperature information signals so as to output a delay control signal. The pulse generator outputs an overdriving pulse signal in response to a sense amplifier driving signal and the delay control signal.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: December 8, 2009
    Assignee: Hynix Semiconductor Inc.
    Inventor: Ho-Uk Song
  • Publication number: 20090295450
    Abstract: A signal processing apparatus is provided, which generates a data signal having a signal waveform corresponding to a first bit value of a signal waveform transitioning from a high level to a low level or a signal waveform transitioning from a low level to a high level, a pre-transition signal level corresponding to a second bit value of one of a plurality of high levels and a plurality of low levels, and a post-transition signal level corresponding to a third bit value of the other.
    Type: Application
    Filed: May 27, 2009
    Publication date: December 3, 2009
    Inventor: Takehiro SUGITA
  • Patent number: 7622973
    Abstract: Provided is a pulse control device is maintained with a constant pulse width corresponding to a change of process or temperature. The pulse control device comprises a fuse set for selectively outputting a delay increase signal and a delay decrease signal that have a different state based on a cutting or non-cutting state of a fuse on which information on a change of process is programmed, and a pulse generator provided with a plurality of delay cells with predetermined time delay for selectively increasing or decreasing the number of the plurality of delay cells depending on the delay increase signal and the delay decrease signal to generate an internal clock with a pulse width corresponding to the number of the increased or decreased delay cells.
    Type: Grant
    Filed: June 30, 2006
    Date of Patent: November 24, 2009
    Assignee: Hynix Semiconductor, Inc.
    Inventors: Kyoung-Nam Kim, Tae-Yun Kim
  • Publication number: 20090284298
    Abstract: A method for automatically adjusting the clock frequency for a USB interface including the steps of: generating a clock signal with an adjustable frequency; receiving a USB differential signal; counting the clock signal based on each frame time of the USB differential signal and obtaining a count value; and adjusting the frequency of the clock signal when the count value exceeds a predetermined count range. The present invention further provides a clock frequency adjusting circuit.
    Type: Application
    Filed: October 30, 2008
    Publication date: November 19, 2009
    Applicant: PIXART IMAGING INC.
    Inventor: Hsiang Sheng LIU
  • Patent number: 7612598
    Abstract: In a semiconductor device capable of radio communication, a stable clock signal is generated even if a reference clock signal for generating a clock signal has varied frequencies in each cycle. A clock signal generation circuit includes an edge detection circuit that detects an edge of an input signal and generates a synchronization signal, a reference clock signal generation circuit that generates a clock signal which functions as reference, a counter circuit that counts the number of edges of rise of the reference clock signal in accordance with the synchronization signal, a duty ratio selection circuit that selects a duty ratio of a clock signal from a count value, and a frequency division circuit that generates the clock signal having the selected duty ratio.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: November 3, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Masami Endo
  • Patent number: 7612597
    Abstract: An electronic circuit for performing clock gating on a clock signal supplied to a clock system using both edges, has a non-inverted/inverted signal selector which has an input connected to an input terminal, is fed with the clock signal through the input terminal, and outputs a first signal obtained by non-inverting or inverting the clock signal in response to a control signal; a signal latch which has an input connected to an output of the non-inverted/inverted signal selector, outputs the inputted first signal as a second signal through an output terminal, and latches a state of the second signal in response to an enable signal inputted through an enable terminal; and an input/output comparator which compares the clock signal and the second signal and outputs the control signal to the non-inverted/inverted signal selector such that the first signal agrees with the second signal.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: November 3, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Shuuji Matsumoto
  • Publication number: 20090267674
    Abstract: A clock control circuit comprises a control signal generating unit configured to generate a control signal disabled in a predetermined state while in an active mode, and a clock transferring unit configured to transfer an external clock in response to the control signal.
    Type: Application
    Filed: August 22, 2008
    Publication date: October 29, 2009
    Inventor: Mi Hyun Hwang
  • Patent number: 7609104
    Abstract: A digitally controlled delay line generates a clock signal. The clock signal can be modulates as a spread spectrum clock signal. In an example embodiment, the programmable delay line has an input for receiving a signal, an output that delays outputting the input signal by a time period programmed into a delay value input. A feedback loop comprising an inverter is coupled between the input and the output of the programmable delay line.
    Type: Grant
    Filed: October 26, 2006
    Date of Patent: October 27, 2009
    Inventor: Masao Kaizuka
  • Publication number: 20090265677
    Abstract: Disclosed are embodiments of a clock generation circuit, a design structure for the circuit and an associated method that provide deskewing functions and that further provide precise timing for both testing and functional operations. Specifically, the embodiments incorporate a deskewer circuit that is capable of receiving waveform signals from both an external waveform generator and an internal waveform generator. The external waveform generator can generate and supply to the deskewer circuit a pair of waveform signals for functional operations. The internal waveform generator can be uniquely configured with control logic and counter logic for generating and supplying a pair of waveform signals to the deskewer circuit for any one of built-in self-test (BIST) operations, macro-test operations, other test operations or functional operations.
    Type: Application
    Filed: April 17, 2008
    Publication date: October 22, 2009
    Inventors: Gary D. Grise, Vikram Iyengar, David E. Lackey, David W. Milton
  • Patent number: 7602226
    Abstract: A method and apparatus for clock generation have been disclosed having a selector logic block that controls operation based upon inputs such as analog input(s), digital input(s), a lookup table, and preset value(s), and combinations of such.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: October 13, 2009
    Assignee: Integrated Device Technology, Inc.
    Inventors: Frank Hwang, Howard Yang, Chuen-Der Lien, Jimmy Lee
  • Publication number: 20090251190
    Abstract: A method and apparatus are disclosed for generating a second clock signal, having a second effective clock frequency, from a first clock signal, having a first effective clock frequency. Clock pulses of the first clock signal are counted to generate a count value. When the count value reaches a predetermined blanking value, a blanking signal is generated. The blanking signal blanks at least one clock pulse of the first clock signal. The process is repeated multiple times at a predetermined rate corresponding to the predetermined blanking value to generate the second clock signal.
    Type: Application
    Filed: December 1, 2008
    Publication date: October 8, 2009
    Inventors: Kang Xiao, Steve Thomas, Robert Holder, Timothy Chan
  • Patent number: 7592843
    Abstract: A clock input filter uses a first programmable low-pass delay element to filter during a low period of an input clock signal and to output a SET signal. The clock input filter uses a second programmable low-pass delay element to filter during a high period of the input clock signal and to output a RESET signal. A latch is set and reset by the SET and RESET signals. The latch outputs a filtered version of the input signal that has the same approximate duty cycle as the input signal. A pair of gates generates a corresponding pair of duty cycle adjusted versions of the input signal. Output multiplexing circuitry is provided to output either the output of the latch, or an increased duty cycle version of the input signal, or a decreased duty cycle version of the input signal, or an unfiltered version of the input signal.
    Type: Grant
    Filed: August 5, 2008
    Date of Patent: September 22, 2009
    Assignee: ZiLOG, Inc.
    Inventor: Steven K. Fong
  • Publication number: 20090219069
    Abstract: Circuit elements and wirings constituting a circuit, and first electrodes electrically connected to such a circuit are provided on one main surface of a semiconductor substrate. An organic insulating film is formed on the circuit except for openings on the surfaces of the first electrodes. First and second external connecting electrodes are provided on the organic insulating film. At least one conductive layer for electrically connecting the first and second external connecting electrodes and the first electrodes is placed on the organic insulating film.
    Type: Application
    Filed: May 8, 2009
    Publication date: September 3, 2009
    Inventors: Masao Shinozaki, Kenji Nishimoto, Takashi Akioka, Yutaka Kohara, Sanae Asari, Shusaku Miyata, Shinji Nakazato
  • Patent number: 7579892
    Abstract: In one embodiment, a reference generator forms a reference signal that may have temperature and process variations. A comparator that has similar variations is used to detect a signal using the reference.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: August 25, 2009
    Assignee: Semiconductor Components Industries, L.L.C.
    Inventor: Petr Kadanka
  • Publication number: 20090201065
    Abstract: A local signal generation circuit in accordance with one aspect of the present invention includes a phase comparator that detects a phase difference between a reference signal and a feedback signal and outputs a error signal, a charge-pump circuit that receives the error signal and generates a step-up voltage, a loop filter that generates a tuning voltage by changing the shape of the step-up voltage, a voltage control oscillator that generates a first output signal having a predefined frequency based on the tuning voltage, and a prescaler that outputs a second output signal generated by dividing the frequency of the first output signal to a predefined frequency and also outputs a frequency-division signal generated by dividing the frequency of the first output signal to the predefined frequency to a frequency divider that generates the feedback signal.
    Type: Application
    Filed: January 13, 2009
    Publication date: August 13, 2009
    Applicant: NEC Electronics Corporation
    Inventors: Akira Kuwano, Toshiyuki Tanaka
  • Publication number: 20090201064
    Abstract: A phase interpolator system is disclosed that may include a clock to provide a clock signal, and a control section in communication with the clock to regulate the strength of the clock signal. The system may also include a generator circuit to produce an alternate clock signal based upon the strength of the clock signal received from the control section.
    Type: Application
    Filed: February 11, 2008
    Publication date: August 13, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Kyu-hyoun Kim, Paul W. Coteus, Daniel M. Dreps, Frank D. Ferrsiolo
  • Publication number: 20090201066
    Abstract: A system and method are provided for controlling the duty cycle and frequency of a digitally generated clock. The method accepts a first clock signal having a fixed first frequency. A frequency control word with a first pattern is loaded into a first plurality of serially-connected registers. A duty cycle control word with a second pattern is loaded into a second plurality of serially-connected registers. A register clock signal is generated in response to the first clock and the first pattern. Then, a digital clock signal is generated having a frequency and duty cycle responsive to the register clock signal and the second pattern.
    Type: Application
    Filed: April 14, 2009
    Publication date: August 13, 2009
    Inventors: Viet Linh Do, Hongming An, Jim Lew
  • Patent number: 7573312
    Abstract: A frequency multiplier increases the frequency of an external clock and outputs a high-frequency external clock. A period determinator determines whether or not a predetermined period of the external clock elapses and outputs a period determination signal. A frequency selector selectively transmits the external clock or the high-frequency external clock to a clock input buffer under the control of a power-up signal and the period determination signal.
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: August 11, 2009
    Assignee: Hynix Semiconductor Inc.
    Inventor: Seong Jun Lee
  • Patent number: 7564286
    Abstract: A clock regeneration circuit includes a half-bit delay device that outputs a half-bit delayed signal B of a multi-level input signal A, a one-bit delay device that outputs a one-bit delayed signal C of the signal A, an adder, an attenuator that forms an threshold signal, an XOR circuit, and a BPF that outputs a clock signal with a frequency corresponding to a bit rate of the XOR signal. The XOR signal is calculated as an XOR of a two-level input signal F, which is a logical zero when a level of the signal A is no more than a level of the threshold signal and otherwise is a logical one, and a two-level input signal G, which is a logical zero when a level of the signal B is no more than the level of the threshold signal and otherwise is a logical one.
    Type: Grant
    Filed: March 4, 2008
    Date of Patent: July 21, 2009
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Hideaki Tamai, Masayuki Kashima
  • Publication number: 20090179681
    Abstract: A semiconductor device includes: a voltage-control-type clock generation circuit having a plurality of stages of first delay elements and whose oscillation frequency is controlled according to a control voltage applied to the first delay elements; a delay circuit having a plurality of stages of second delay elements connected serially; and a selection circuit selecting one from pulse signals output by the plurality of stages of respective second delay elements. The first delay elements and the second delay elements have a same structure formed on a same semiconductor substrate, and a delay amount of the second delay elements is adjusted according to the control voltage.
    Type: Application
    Filed: January 9, 2009
    Publication date: July 16, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kazutoshi Nakamura, Toru Takayama, Yuki Kamata, Akio Nakagawa, Yoshinobu Sano, Toshiyuki Naka
  • Patent number: 7557632
    Abstract: An internal clock generator includes a detector, an internal signal generator and a clock output unit. The detector detects a transition point of an external clock signal and outputting a detection signal. The internal signal generator generates an internal signal in response to the detection signal and a pulse width control signal. The clock output unit outputs an internal clock signal having a pulse width, which is set based on the internal signal. A transition point of an external clock signal is detected and an internal clock signal is generated based on the detection result. It is therefore possible to maintain the pulse width of the internal clock signal to a set value regardless of variation in the pulse width of the external clock signal.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: July 7, 2009
    Assignee: Hynix Semiconductor Inc.
    Inventor: Chang Il Kim
  • Publication number: 20090167401
    Abstract: A system for providing a plurality of synchronous timing signals having period values that are not even multiples of the clock period including a plurality of local edge generators receiving the clock signals, each local generator including local programmable means to record an absolute time at which to generate a timing signal in the current or future period and the means to generate that timing signal at a synchronous even sub-division of the clock period resolution. A separate time value is maintained allowing generated timing signals to be delayed by more than one period. An output delay circuit generates the timing signal responsive to a future time value and a phase offset. The phase offset can be provided using a clock multiplier and serial parallel converter to simplify hardware realizations.
    Type: Application
    Filed: December 18, 2008
    Publication date: July 2, 2009
    Applicant: Teradyne, Inc.
    Inventors: Christopher C. JONES, Michael F. MCGOLDRICK
  • Patent number: 7551016
    Abstract: An apparatus and method for generating local clock signals from system clock signals based upon user inputs that provide a frequency multiplier and a frequency divider. The frequency multiplier and frequency divider are stored in an interface. System clock signals are received and local clock signals are generated by the circuitry. The frequency of the local clock signals is equal to the frequency of the system clock signals multiplied by the frequency multiplier and divided by the frequency divider multiplied by two.
    Type: Grant
    Filed: February 4, 2005
    Date of Patent: June 23, 2009
    Assignee: Atmel Corporation
    Inventor: Rocendo Bracamontes del Toro
  • Publication number: 20090121768
    Abstract: Semiconductor device and operation method thereof includes an aspect of the present invention, there is provided a clock generator configured to receive an external clock signal to generate a first clock signal corresponding to a rising edge of the external clock and a second clock signal corresponding to a falling edge of the external clock, a drive control signal generator configured to restrict an activation period of the first clock signal within a deactivation period of the second clock signal to generate a first drive control signal, and restrict an activation period of the second clock signal within a deactivation period of the first clock signal to generate a second drive control signal and an output driver configured to receive a drive data in response to the first and second drive control signal to drive an output terminal in response to the drive data.
    Type: Application
    Filed: June 9, 2008
    Publication date: May 14, 2009
    Inventor: Sang-Hee Lee
  • Patent number: 7532043
    Abstract: The present disclosure relates to a system, apparatus and method for a line driver circuit to generate a signal detect (SD) signal when an invalid data signal is detected at its input. An invalid signal may be present either when no signal is available or when the line driver circuit or another component in the system (e.g., a crosspoint switch, a multiplexer, etc.) fails. The SD signal is coupled to an external controller that can either power down the line driver circuit to save power when no signal is available, or change over to a different line driver circuit or other component of the system when a failure is identified. When the input signal is determined to be a valid data signal via the SD signal, the line driver circuit can be enabled for operation. The described systems, apparatus and methods can save the user from having to directly control the line driver power state, especially in systems with large router configurations that may include hundreds of line drivers.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: May 12, 2009
    Assignee: National Semiconductor Corporation
    Inventor: Robert Karl Butler
  • Patent number: 7514977
    Abstract: A clock signal generating circuit is provided. The clock signal generating circuit includes a clock signal generator for generating a first clock signal having a predetermined frequency; a frequency dividing circuit receiving the first clock signal, for providing a second clock signal with a frequency that is lower than the predetermined frequency of the first clock signal; and a frequency multiplier circuit receiving the second clock signal, for providing a system clock signal resuming the predetermined frequency to a load.
    Type: Grant
    Filed: September 1, 2006
    Date of Patent: April 7, 2009
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventor: Chun-Hung Chen
  • Patent number: 7514976
    Abstract: A pulsed flip-flop capable of adjusting a pulse width according to an operating voltage includes: a flip-flop operating in synchronization with a pulse signal; a pulse generating circuit generating the pulse signal in response to a clock signal; and a pulse width control circuit reducing a width of the pulse signal generated by the pulse generating circuit when the operating voltage is lower than a reference voltage.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: April 7, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Kwang-Il Kim
  • Publication number: 20090085631
    Abstract: Clock control is handed over in a bus circuit from a first circuit (14) to a second circuit (12). A clock conductor (10a) is driven to a predetermined voltage level with the driver circuit of the first circuit after a last clock period following the start of execution of the handover command and to continue driving the clock conductor (10a) to the predetermined voltage level for a first time-interval. The clock conductor (10a) is driven to the predetermined voltage level with the driver circuit of the second circuit after a second time interval following the start of execution of the handover command until a third time interval has elapsed following the end of the second time interval. Subsequently the clock conductor (10a) is driven under control of the clock circuit (140) of the second circuit (14).
    Type: Application
    Filed: September 21, 2006
    Publication date: April 2, 2009
    Applicant: NXP B.V.
    Inventors: Xavier Lambrecht, Bernardus Adrianus Cornelis Van Vlimmeren
  • Publication number: 20090085630
    Abstract: A clock circuit includes a waveform generator, a comparison module, and a clock signal module. The waveform generator is coupled to generate a waveform based on a reference oscillation. The comparison module is coupled to compare the waveform with a plurality of references to produce a plurality of waveform comparisons. The clock signal module is coupled to generate a clock signal from the plurality of waveform comparisons.
    Type: Application
    Filed: September 28, 2007
    Publication date: April 2, 2009
    Applicant: BROADCOM CORPORATION
    Inventor: Nikolaos Haralabidis
  • Publication number: 20090039941
    Abstract: A memory clock signal is generated in response to a reference clock signal and a clock enable signal. The memory clock signal with a frequency identical to that of the reference clock signal is generated during the clock enable signal is in an enabled state; and the memory clock signal with a reduced frequency is generated when the clock enable signal is changed from the enabled state to a disabled state. The generation of a memory clock signal is adaptive so as to save power.
    Type: Application
    Filed: July 3, 2008
    Publication date: February 12, 2009
    Applicant: VIA TECHNOLOGIES, INC.
    Inventor: Chi Chang
  • Patent number: 7466180
    Abstract: A clock network comprises a clock distribution path coupled to a circuit. The clock distribution path and the circuit are formed on a substrate. The clock distribution path comprises a plurality of interconnected elements and one or more disconnected elements. The disconnected elements can be connected to the plurality of interconnected elements after the clock distribution path is tested in connection with the circuit. In one embodiment, the disconnected elements include a capacitor, an interconnect, and a buffer. In an alternative embodiment, the plurality of interconnected elements include a buffer, an interconnect and a capacitor.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: December 16, 2008
    Assignee: Intel Corporation
    Inventor: Darren Slawecki
  • Publication number: 20080303576
    Abstract: Disclosed herein is a digital system that includes a distribution network to carry a reference clock, and a circuit domain coupled to the distribution network to receive the reference clock for synchronous operation in accordance with the reference clock. The circuit domain includes a clock generator driven by the reference clock to generate a resonant clock signal, an input port to receive a control signal, and a gate coupled to the input port to discontinue application of the resonant clock signal within the circuit domain based on the control signal.
    Type: Application
    Filed: December 3, 2007
    Publication date: December 11, 2008
    Applicant: THE REGENTS OF THE UNIVERSITY OF MICHIGAN
    Inventors: Juang-Ying Chueh, Jerry Kao, Visvesh Sathe, Marios C. Papaefthymiou
  • Patent number: 7463077
    Abstract: A device for generating a periodic clock signal according to the invention comprises a bandpass filter is disclosed. In one embodiment, the bandpass filter includes a bandpass filter input for receiving an input signal and a bandpass filter output for outputting a bandpass filter signal. The device includes further a comparator. A comparator has at least one comparator input receiving the bandpass filtered signal and a comparator output for outputting the clock signal. The comparator is adapted to output a first signal level at the comparator output, if the bandpass filtered signal exceeds a reference level. A zero crossing of the bandpass filtered signal may be used as reference level. A second signal level is output at the comparator output if the bandpass filter signal falls below the reference level. The output signal of the comparator is the clock signal.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: December 9, 2008
    Assignee: Infineon Technologies AG
    Inventor: Stefan Hermann Groiβ
  • Patent number: 7456674
    Abstract: Disclosed is a clock generation circuit for generating a clock-out signal that has a fixed latency with respect to a clock-input signal. When multiple such clock generation circuits are utilized to feed clock signals to different digital logic circuits within an integrated circuit structure, differences in delay time, referred to as skew, are minimized. An embodiment of the clock generation circuit incorporates a waveform generator and a timing-improved deskewer. The waveform generator is clocked by a clock-in signal. The deskewer comprises a flip-flop, a level-sensitive latch, and a multiplexer. The flip-flop and latch are connected in parallel and each receives waveform signals from the waveform generator as well as the clock-in signal in order to generate output signals. The multiplexer gates the flip-flop and latch output signals with the clock-in signal in order to generate the clock-out signal. A testable deskewer for edge-sensitive multiplexer scan designs is also disclosed.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: November 25, 2008
    Assignee: International Business Machines Corporation
    Inventor: Steven F. Oakland
  • Publication number: 20080272820
    Abstract: A method, an apparatus, and a computer program are provided to reduce transient current swings during mode transitions. Traditionally, transient supply voltage fluctuations on a chip account for a large portion of the power supply. The number of series inductances and resistances are typically minimized, while adding large decoupling capacitances between the supply voltage and ground. However, situations may arise where reduction of series inductances and resistances cannot be accomplished. Therefore, to assist in controlling the transient current swings, reduction of clocking frequencies are performed in a controlled manner.
    Type: Application
    Filed: June 4, 2008
    Publication date: November 6, 2008
    Applicant: International Business Machines Corporation
    Inventors: David William Boerstler, Eskinder Hailu, Mack Wayne Riley, Michael Fan Wang
  • Patent number: 7446589
    Abstract: Pulse generation circuit has a P-MOS transistor having a drain electrode connected to a first power source; a first N-MOS transistor having a drain electrode connected to the source electrode of the P-MOS transistor; a second N-MOS transistor having a drain electrode connected to the source electrode of the first N-MOS transistor, a gate electrode receiving an input pulse signal, and a source electrode connected to the second power source; a delay circuit having an input terminal connected to the source electrode of the P-MOS transistor and the drain electrode of the first N-MOS transistor and an output terminal connected to gate electrode of the P-MOS transistor and gate electrode of the first N-MOS transistor; an inverter input connected to the source electrode of the P-MOS transistor and the drain electrode of the second N-MOS transistor for outputting a generated pulse; and a keeper keeping voltage level to the inverter.
    Type: Grant
    Filed: December 29, 2005
    Date of Patent: November 4, 2008
    Assignee: Fujitsu Limited
    Inventor: Kenji Ijitsu
  • Patent number: 7446586
    Abstract: The disclosure is directed to an internal pulse generator outputting a signal with a constant pulse width nevertheless of a frequency of an input signal, including a first PMOS transistor, a PMOS second transistor and an NMOS transistor which are connected between a power supply voltage and a ground voltage in series, a latch and an inverter which are connected between an output terminal and a first node as a drain of the NMOS transistor, and a Y-time delay circuit connected between the output terminal and a second node that is a common gate of the PMOS and NMOS transistors.
    Type: Grant
    Filed: March 16, 2007
    Date of Patent: November 4, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventor: Nak Kyu Park