Plural Outputs Patents (Class 327/295)
  • Publication number: 20080265967
    Abstract: A device for generating clock signals for use with a plurality of DDR memory devices on a dual in-line memory module (DIMM) board is provided that has a data buffer for buffering data. A clock divider divides a first clock signal (CLK1) having a first clock frequency to generate a second clock signal (CLK20) having a second clock frequency which is an integer multiple of the first clock frequency. A shift register (SH) receives the second clock signal as a data input signal, and comprises a plurality flip-flops having clock inputs coupled to receive the first clock signal (CLK1), and further coupled so that the data output of a preceding flip-flop is coupled to be the data input of a following flip-flop. The second clock signal is shifted through the shift register (SH) in response to the first clock signal (CLK1) to generate a plurality of shifted clock signals (CLK 21, . . . , CLK32) at respective data outputs of the plurality of flip-flops.
    Type: Application
    Filed: April 28, 2008
    Publication date: October 30, 2008
    Applicant: TEXAS INSTRUMENTS DEUTSCHLAND GMBH
    Inventor: Joerg Goller
  • Patent number: 7414451
    Abstract: The clock generator for semiconductor memory apparatus which includes: a first divider; a first delay unit; a second divider; a second delay unit; a duty-cycle corrector; a third divider; a third delay unit; a phase comparator; and a delay time setting unit. The clock generator for semiconductor memory apparatus exactly performs phase correction and duty cycle correction using frequency-divided clocks. Therefore, it is possible to generate reliable clocks and to improve the operational performance of a system using the clock generator.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: August 19, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventor: Hyun-Woo Lee
  • Patent number: 7411437
    Abstract: Generally, the embodiments presented are directed to circuits and methods for triggering an event at a fraction of a clock cycle. A triggering circuit can comprise two or more input circuits that output an event signal. The event signal is received by one of two or more delay circuits that trigger the event signal at a predetermined phase of the clock cycle by moving the event signal from a first clock domain to another clock domain. By triggering the event at a phase division, the triggering circuit outputs signals at a rate faster than the clock cycle.
    Type: Grant
    Filed: December 2, 2005
    Date of Patent: August 12, 2008
    Assignee: Agilent Technologies, Inc.
    Inventors: Dietrich Werner Vook, Vamsi Krishna Srikantam, Andrew Fernandez
  • Publication number: 20080186074
    Abstract: A configured setting circuit and method thereof is disclosed. The configured setting circuit includes a multi-phase clock generator, a plurality of terminals, and a decision circuit. The multi-phase clock generator generates a plurality of multi-phase signals with different phases to be outputted via the terminals. The decision circuit detects a phase difference between the input signal and the reference signal and outputs a configuration data according to the phase difference between the input signal and the reference signal.
    Type: Application
    Filed: February 4, 2008
    Publication date: August 7, 2008
    Inventor: Ming-Yuh Yeh
  • Publication number: 20080180155
    Abstract: A data output clock generating circuit for a semiconductor memory apparatus includes a rising data output clock generating unit configured to combine a rising clock with a rising clock extraction signal generated in response to a rising output enable signal and a falling clock, to generate a rising data output clock; and a falling data output clock generating unit configured to combine the falling clock with a falling clock extraction signal generated in response to a falling output enable signal and the rising clock, to generate a falling data output clock; wherein the rising data output clock generating unit and the falling data output clock generating unit are independently driven in parallel.
    Type: Application
    Filed: March 20, 2008
    Publication date: July 31, 2008
    Applicant: Hynix Semiconductor Inc.
    Inventor: Geun Il LEE
  • Patent number: 7405607
    Abstract: A clock generation circuit receives a reference clock signal for outputting clock signals to peripheral circuits. A duty ratio of at least one of output buffer signals output from buffer circuits included in the clock generation circuit is varied so that a duty ratio of at least one of the clock signals can be varied.
    Type: Grant
    Filed: May 15, 2007
    Date of Patent: July 29, 2008
    Assignee: Renesas Technology Corp.
    Inventor: Koichi Ishimi
  • Patent number: 7403074
    Abstract: An oscillator, generating multiple phases of clock signals having a uniform phase difference with a high precision by a simple configuration, includes a plurality of NAND circuits ND1 to ND8 having the same number of input terminals connected in a ring. Eight NAND circuits are connected, and an output node of each NAND circuit is connected to an input node of each NAND circuit up to the NAND circuit connected exactly two places, that is, the number of input terminals' worth of places, ahead.
    Type: Grant
    Filed: February 26, 2004
    Date of Patent: July 22, 2008
    Assignee: Sony Corporation
    Inventor: Naoki Takahashi
  • Publication number: 20080169848
    Abstract: A novel clock splitter that has a local internal clock frequency-divider is presented. The clock splitter comprises an oscillator clock splitter, wherein the oscillator clock splitter splits an oscillator clock signal into a B clock and a C clock; a clock frequency-divider, wherein the clock frequency-divider selectively suppresses clock pulses in the C clock to generate a slower C clock signal that is slower than the oscillator clock; and a B/C clock order logic, wherein the B/C clock order logic phase shifts the C clock relative to a B clock. The clock frequency-divider may selectively suppress pulses in the B clock to generate a slower B clock signal. The slower B and C clock signals may have a same or different frequency. In one embodiment, the clock splitter is located at a terminal leaf of a clock tree.
    Type: Application
    Filed: January 17, 2007
    Publication date: July 17, 2008
    Inventors: Steven Michael Douskey, Matthew Roger Ellavsky
  • Publication number: 20080164927
    Abstract: A signal generator and method for generating a plurality of signals of differing phase. The signal generator comprises a first single-phase frequency divider locked with a 90° phase shift that includes a first output port providing a first output signal and a first internal node providing a first internal signal, a second single-phase frequency divider locked with a 90° phase shift that includes a second output port providing a second output signal and a second internal node providing a second internal signal, and a first feedback circuit. The first feedback circuit coupled between either: first and second output ports or first and second internal nodes. The first feedback circuit configured to phase-lock first and second output signals 180° apart when the first feedback circuit is coupled between first and second outputs ports and phase-lock first and second internal signals 180° apart when the first feedback circuit is coupled between first and second internal nodes.
    Type: Application
    Filed: January 9, 2007
    Publication date: July 10, 2008
    Applicant: International Business Machines Corporation
    Inventor: Xudong Wang
  • Patent number: 7397288
    Abstract: In one embodiment, a fan out buffer has the inputs of a plurality of output followers connected to the output of a plurality of distribution gates.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: July 8, 2008
    Assignee: Semiconductor Components Industries, L.L.C.
    Inventor: Ira E. Baskett
  • Publication number: 20080158035
    Abstract: A first Delayed Flip Flop includes a first D input terminal, a first clock input terminal, a first output terminal outputting a signal inputted to the first D input terminal based on the clock signal, and a first inversion output terminal inverting and outputting the signal inputted to the first D input terminal and outputting the signal to the first D input terminal as a feedback. A second Delayed Flip Flop includes a second D input terminal receiving the output from the first output terminal of the first Delayed Flip Flop, a second clock input terminal, and a second output terminal outputting the signal inputted to the second D input terminal as a first output based on the clock signal. A third Delayed Flip Flop includes a third D input terminal receiving the output from the first inversion output terminal of the first Delayed Flip Flop, a third clock input terminal, and a third output terminal outputting the signal inputted to the third D input terminal as a second output based on the clock signal.
    Type: Application
    Filed: December 27, 2007
    Publication date: July 3, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshikazu Makabe, Ikuo Hidaka, Koji Oka, Toshiaki Ozeki
  • Patent number: 7394303
    Abstract: An exemplary embodiment of the present invention provides a pulse generator generating a control signal to control a latch unit included in a source driver for sequentially latching input data applied to a source data line of a display device, wherein the pulse generator includes a latch circuit latching an input signal in response to an N-divided clock signal and applying the latched input signal as an output signal, and a logic unit generating a pulse signal by logically multiplying the input signal by the N-divided clock signal, wherein the output signal is provided as an input signal to the latch circuit of another pulse generator, and the pulse signal is provided to the latch unit as the control signal.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: July 1, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Do-Kyung Kim, Jung-Bong Lee, Hyun-Young Park
  • Publication number: 20080143416
    Abstract: A clock distribution network, structure, and method for providing balanced loading is disclosed. In particular, a clock distribution network may be formed of one or more clock fanout distribution levels. Each respective distribution level may include an equal number of buffer circuits and wiring routes that have substantially identical physical and electrical properties. Additionally, a final distribution level may include wiring routes that have substantially identical physical and electrical properties connecting buffer circuits to one or more logic leaf connection nodes.
    Type: Application
    Filed: December 14, 2006
    Publication date: June 19, 2008
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Serafino Bueti, Hayden C. Cranford, Joseph A. Iadanza, Pradeep Thiagarajan, Sebastian T. Ventrone
  • Patent number: 7385430
    Abstract: A data output clock generating circuit for a semiconductor memory apparatus includes a rising data output clock generating unit which combines a rising clock with a signal to be generated in response to a rising output enable signal and a falling clock to generate a rising data output clock, and a falling data output clock generating unit which combines the falling clock with a signal to be generated in response to a falling output enable signal and the rising clock to generate a falling data output clock.
    Type: Grant
    Filed: November 3, 2006
    Date of Patent: June 10, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventor: Geun-Il Lee
  • Patent number: 7383373
    Abstract: Apparatus used in deriving corresponding signals includes first and second circuitry. The first circuitry derives, from a source-terminated first signal driven from a Peripheral Control Interface (PCI) Express compatible source, an AC-coupled second signal. The second circuitry derives, from the AC-coupled second signal, a destination-terminated DC biased third signal that drives a pseudo-emitter-coupled logic (PECL) compatible receiver.
    Type: Grant
    Filed: March 21, 2006
    Date of Patent: June 3, 2008
    Assignee: EMC Corporation
    Inventor: Stephen E. Strickland
  • Publication number: 20080116811
    Abstract: A plasma display device and a power supply, having advantages of performing a normal AC voltage detection operation regardless of a peripheral temperature is disclosed. The use of passive elements allows for temperature invariance.
    Type: Application
    Filed: July 17, 2007
    Publication date: May 22, 2008
    Inventor: Il-Woon Lee
  • Patent number: 7368961
    Abstract: A clock distribution network locks a local clock signal to a reference clock signal using a first feedback loop associated with a synchronization circuit (e.g., a PLL or a DLL). The local clock signal can then be selectively distributed to a plurality of clock destination nodes via a clock network. Clock distribution may be disabled as needed to save power. The first feedback loop is active irrespective of whether clock distribution is enabled. The delay through the clock network may drift due to temperature and supply-voltage fluctuations, which introduces phase errors in the distributed clock signals. A second feedback loop is activated when clock distribution is enabled to compensate for this drift.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: May 6, 2008
    Assignee: Rambus Inc.
    Inventors: Carl Werner, Ely Tsern
  • Patent number: 7368953
    Abstract: A buffer is disclosed. The buffer may include a buffer controller for buffering a refresh signal enabled in an auto-refresh operation synchronously with an external clock signal, a logic circuit for performing a logic operation with respect to an output signal from the buffer controller and a specific signal to output a control signal, and an internal clock generator controlled by the control signal from the logic circuit for buffering the external clock signal and generating internal clock signals.
    Type: Grant
    Filed: January 6, 2006
    Date of Patent: May 6, 2008
    Assignee: Hynix Semiconductor Inc.
    Inventors: Shin Ho Chu, Sun Mo An
  • Patent number: 7368945
    Abstract: When a buffer is formed by using transistors having large element characteristic variations, the deviation of the timing between the input clock pulse and the reset pulse is likely to occur. When the deviation of the timing becomes larger, a malfunction is caused to occur, and an operation margin becomes smaller with respect to the variations of the element characteristics. In a timing generation circuit, which is formed on an insulating substrate and which has two TFFs (12, 13), for generating a dot clock DCK and a horizontal clock HCK whose frequencies are different in synchronization with a master clock MCK which is input external to the substrate, separate reset pulses drst and hrst are generated at a pulse generation circuit 15 with respect to the two TFFs (12, 13), and a resetting operation is performed at separate timings. Thus, a large operation margin can be ensured even when each circuit is formed by using TFTs having large element characteristic variations and a rough process rule.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: May 6, 2008
    Assignee: Sony Corporation
    Inventors: Yoshitoshi Kida, Yoshiharu Nakajima, Toshikazu Maekawa
  • Patent number: 7352059
    Abstract: A low loss on-die interconnect structure includes first and second differential signal lines on one of the metal layers of a microelectronic die. One or more traces may also be provided on another metal layer of the die that are non-parallel (e.g., orthogonal) to the differential signal lines. Because the traces are non-parallel, they provide a relatively high impedance return path for signals on the differential signal lines. Thus, a signal return path through the opposite differential line predominates for the signals on the differential lines. In one application, the low loss interconnect structure is used within an on-die salphasic clock distribution network.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: April 1, 2008
    Assignee: Intel Corporation
    Inventors: Frank O'Mahony, Mark A. Anders, Krishnamurthy Soumyanath
  • Patent number: 7342430
    Abstract: Present invention provides a method and apparatus for generating multiple phase shifted clocks with clocks delayed from EFM clock.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: March 11, 2008
    Inventor: Kevin Chiang
  • Patent number: 7336115
    Abstract: A signal distribution tree structure for distributing signals within a plurality of signal tree branches to a plurality of signal sinks, wherein the signal in subsequent sub trees (11) is driven by a preceding amplifier (2), which is characterized in that the amplifiers are logic gates (3), which combines the signals of a preferred input (31) connected to a preceding logic gate in the signal path with a signal of a secondary input (32) connected to an adjacent tree (12) path of a neighboring and/or preceding sub tree.
    Type: Grant
    Filed: February 8, 2006
    Date of Patent: February 26, 2008
    Assignee: International Business Machines Corporation
    Inventors: Sebastian Ehrenreich, Juergen Koehl, Juergen Pille
  • Patent number: 7336116
    Abstract: The clock supply circuit of the present invention comprises a plurality of clock supply paths and a clock gate circuit. The clock supply paths branch a clock signal and supply each of the branched clock signals to a plurality of sequential circuits via a buffer. The clock gate circuit is inserted at least to one of the clock supply paths, which lets through the clock signals when a control signal is in a first logic state and, when the control signal is in a second logic state, outputs an inversion signal of a logic level that is outputted in a previous occasion where the control signal in the second logic state is applied.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: February 26, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akio Hirata, Takahiro Ichinomiya, Takashi Ando
  • Patent number: 7323921
    Abstract: A system on a chip integrated circuit includes a first circuit module and N other circuit modules that are operable to produce at least one output signal based on at least one input signal. A reference oscillator for generating a base clock signal for the first circuit module. A clock delay generator generates N delayed clock signals at a corresponding N clock delays, wherein N is greater than or equal to 2. The N delayed clock signals are provided to the N other circuit modules.
    Type: Grant
    Filed: November 22, 2005
    Date of Patent: January 29, 2008
    Assignee: Sigmatel, Inc.
    Inventors: Erich Lowe, Michael R. May
  • Patent number: 7319345
    Abstract: A wide-range multi-phase clock generator having a first clock generating circuit, a frequency divider circuit, and a plurality of multiplexers. The first clock generating circuit generates a plurality of first clock signals, each having a first frequency and a respective one of a plurality of different phase angles. The frequency divider circuit receives the plurality of first clock signals from the first clock generating circuit, and generates a plurality of second clock signals, each having a second frequency and a respective one of the plurality of different phase angles. The multiplexers each have a first input coupled to receive a respective one of the first clock signals and a second input coupled to receive a respective one of the second clock signals having substantially the same phase angle as the one of the first clock signals.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: January 15, 2008
    Assignee: Rambus Inc.
    Inventors: Ramin Farjad-rad, John W. Poulton, John Eble, Thomas H. Greer, III, Robert Palmer
  • Patent number: 7317343
    Abstract: In one embodiment of the invention, a pulse-generation circuit for generating control signals has clock-delay circuitry for generating a plurality of differently delayed clock signals. Each control signal is generated by a set-reset latch that receives its set and reset signals from different pulse generators operating based on different delayed clock signals from the clock-delay circuitry. In one implementation, the clock-delay circuitry has a partitioned delay block in which different sub-blocks provide different delay functionality to provide the clock-delay circuitry with programmable flexibility.
    Type: Grant
    Filed: October 25, 2005
    Date of Patent: January 8, 2008
    Assignee: Lattice Semiconductor Corporation
    Inventors: Louis De La Cruz, Hemanshu T. Vernenker
  • Patent number: 7317342
    Abstract: A clock distribution network for clock distribution in an integrated circuit (IC) using digital feedback for skew compensation and jitter filtering. In an embodiment, a number of clock processor nodes are distributed throughout the clock distribution network on the IC at respective local clock regions. A master clock generator generates a master clock for distribution to the clock processor nodes, via the clock distribution network, to compensate clock skew and filter clock jitter locally at the respective local clock regions.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: January 8, 2008
    Assignee: Intel Corporation
    Inventor: Martin Saint-Laurent
  • Patent number: 7310011
    Abstract: The present invention relates to a clock signal distribution circuit for distributing the clock signal to circuits such as LSI integrated circuits, and, more specifically, provides a clock adjuster circuit, which performs phase difference adjustment of clock signals automatically. It is a circuit, which on driving a circuit element implemented on an LSI chip, supplies the clock signal, which is a reference for driving, is distributed subsequently from first distribution to lower-level distributions of a hierarchical structure, or from a fifth level distribution circuit “5” to every area on the LSI chip, for example. At that time, delay of the clock signal is detected by a phase difference detector circuit, the delay data is automatically written to a delay adjuster circuit built into each of the fifth level distribution circuits “5”. Using the delay data, the phase difference of the clock signals, is adjusted when the LSI chip is manufactured.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: December 18, 2007
    Assignee: Fujitsu Limited
    Inventor: Katsunao Kanari
  • Publication number: 20070252632
    Abstract: A clock distribution circuit for distributing an input clock according to an embodiment of the present invention includes: a first clock buffer receiving the clock; a first clock mask series-connected to the first clock buffer and controlling clock input to the first clock buffer; a second clock buffer series-connected to the first clock buffer and receiving a clock output from the first clock mask; and a second clock mask series-connected to the first clock buffer and the second clock buffer to control clock input to the second clock buffer.
    Type: Application
    Filed: April 25, 2007
    Publication date: November 1, 2007
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Shinichi Shionoya
  • Patent number: 7289572
    Abstract: A system and method for a predriver and driver interface having scalable output drive capability with corresponding scalable power is disclosed.
    Type: Grant
    Filed: October 7, 2002
    Date of Patent: October 30, 2007
    Assignee: International Business Machines Corporation
    Inventors: Hayden C. Cranford, Jr., Westerfield J. Ficken
  • Patent number: 7276942
    Abstract: A method and a system for configurably generating enabling pulse clocks are disclosed herein. In various embodiments, enabling pulse clocks are configurably generated for a selected one of a first and a second signaling mode, employing a configurable enabling pulse clock generator configurable to so generate the enabling pulse clocks.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: October 2, 2007
    Assignee: Intel Corporation
    Inventors: Ying Cole, Songmin Kim, Robert Greiner
  • Patent number: 7276949
    Abstract: A first-phase clock signal is generated in response to a first input clock signal. A second-phase clock signal is generated one clock cycle of the first input clock signal after generating the first-phase clock signal in response to the first input clock signal. A third-phase clock signal is generated one and one half clock cycles of the first input clock signal after generating the second-phase clock signal in response to a second input clock signal. A fourth-phase clock signal is generated one clock cycle of the first input clock signal after generating the third-phase clock signal in response to the second input clock signal.
    Type: Grant
    Filed: February 8, 2006
    Date of Patent: October 2, 2007
    Assignee: Micron Technology, Inc.
    Inventor: Brian Johnson
  • Patent number: 7268605
    Abstract: A technique for operating a delay circuit is disclosed. In one particular exemplary embodiment, the technique may be realized by a delay circuit comprising a plurality of data paths. The delay circuit may receive a signal. The delay circuit may also stagger transmissions of the signal through the plurality of data paths. The delay circuit may additionally generate a plurality of signals based on the staggered transmissions. Each of the plurality of data paths in the delay circuit may comprise at least one of an inverter, a logic gate, a flip-flop, a latch, a register, or a resistor-capacitor (RC) delay element.
    Type: Grant
    Filed: June 14, 2004
    Date of Patent: September 11, 2007
    Assignee: Rambus, Inc.
    Inventors: Wayne Fang, Wayne S. Richardson, Anthony Wong
  • Publication number: 20070182475
    Abstract: This invention provides a technique for enhancing an operating frequency and improving reliability in a system using at least level sense type sequence circuits as a plurality of sequence circuits. A microcomputer includes a clock generator configured as a clock supply source, functional modules operated in sync with a clock signal, level sense type sequence circuits which are contained in the functional modules and configured as clock supply destinations, a clock supply system which propagates the clock signal to the level sense type sequence circuits, etc. The clock supply system includes a clock wiring which propagates the clock signal outputted from the clock generator to ends thereof via a plurality of branches. At least pulse generators are disposed in the midstream of the clock wiring. Each of the pulse generators varies timing provided to change the falling edge of the clock signal, which defines an endpoint of an input operating period of each level sense type sequence circuit.
    Type: Application
    Filed: December 15, 2006
    Publication date: August 9, 2007
    Inventor: Yasuhisa Shimazaki
  • Patent number: 7253673
    Abstract: The present invention discloses a multi-phase clock generator of a network controller for generating a set of multi-phase clocks, and a method thereof. The multi-phase clock generator includes a first gating element and a second gating element. The first gating element operates according to a first control clock and generates a first output clock of the set of multi-phase clocks according to an input clock. The second gating element operates according to a second control clock and generates a second output clock of the set of multi-phase clocks according to the first output clock. The second control clock is an inverted signal of the first control clock.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: August 7, 2007
    Assignee: Realtek Semiconductor Corp.
    Inventor: Shian-Ru Lin
  • Publication number: 20070170970
    Abstract: There is provided a semiconductor device that operates at an internal clock based on a system clock and inputs/outputs data in synchronization with the internal clock. The semiconductor device includes a phase locked loop generating the internal clock and a switching element switching delay paths to be inserted into a feedback loop to the phase locked loop in accordance with data input/output in the semiconductor device.
    Type: Application
    Filed: January 22, 2007
    Publication date: July 26, 2007
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Toshio ISONO
  • Patent number: 7248848
    Abstract: A communication apparatus includes a radio frequency circuit that operates on a radio frequency signal and a digital processing circuit coupled to the radio frequency circuit. The digital processing circuit includes a first timing circuit that provides timed signals to control timing of system operations during an active mode of operation of the digital processing circuit, and a second timing circuit that provides timing signals to control timing of system operations during an active mode of operation of the radio frequency circuit. In one particular embodiment, at least a portion of the first timing circuit is disabled when the radio frequency circuit is active (receiving and/or transmitting).
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: July 24, 2007
    Inventors: Phillip M. Matthews, Frederick A. Rush, G. Diwakar Vishakhadatta
  • Patent number: 7245240
    Abstract: Integrated circuit serializer circuitry is provided that converts parallel data to serial data on an integrated circuit. A two-phase global serializer master clock generator uses a four-phase internal clock to generate a two-phase global serializer master clock. The two-phase global serializer master clock is distributed globally on the integrated circuit using a distribution path. The integrated circuit has multiple serial communications channels each of which has an associated serializer. Each serializer contains circuitry that derives a number of clock signals from the two phases of the global serializer master clock. Each serializer uses the derived clocks in converting parallel data to serial data for transmission over its associated serial communications channel. The serializers each contain two smaller serializers that convert first and second sets of parallel data to first and second serial outputs. A 2:1 serializer in each serializer merges the first and second serial outputs.
    Type: Grant
    Filed: March 7, 2006
    Date of Patent: July 17, 2007
    Assignee: Altera Corporation
    Inventors: Toan Thanh Nguyen, Thungoc M. Tran, Sergey Shumarayev
  • Publication number: 20070159226
    Abstract: A clock generator includes a first circuit, a second circuit, and a third circuit. The first circuit generates a first clock signal. The second circuit divides the frequency of the first clock signal to generate a second clock signal. The third circuit generates a third clock signal from the first and second clock signals. The third clock signal has the same period as that of the second clock signal, and timing at which the third clock signal changes from a first logic level to a second logic level coincides with timing at which the first clock signal changes from a first logic level to a second logic level.
    Type: Application
    Filed: January 4, 2007
    Publication date: July 12, 2007
    Inventor: Nobuhiro Hayakawa
  • Patent number: 7236040
    Abstract: A multiphase clock generating circuit includes a multiphase clock generator that produces a plurality of multiphase output signals at a first frequency and a multiphase divider with delayed reset control. The multiphase divider with delayed reset control is operatively coupled to receive the plurality of multiphase output signals at the first frequency and further operative to produce a plurality of multiphase output signals at a second frequency based on reset control information. As a result, an interface can be supplied with and switch between multiphase clock at different frequencies within a short amount of time with reduced power consumption and circuit area.
    Type: Grant
    Filed: December 3, 2004
    Date of Patent: June 26, 2007
    Assignee: ATI Technologies Inc.
    Inventors: Ronny C. Chan, Mikhail Rodionov, Karen Wan, Richard W. Fung, Paul Edelshteyn, Ramesh Senthinathan
  • Patent number: 7236035
    Abstract: A first logic circuit has its supply voltage controlled. A second logic circuit operates in response to an external clock signal. An adjustment circuit includes a first delay circuit supplied with the external clock signal, and a detection circuit which detects a skew between timing of a first clock signal output from the first logic circuit and a second clock signal output from the second logic circuit section. The adjustment circuit adjusts the delay time of the first delay circuit according to the result of the detection by the detection circuit and applies an output signal of the first delay circuit to the first logic circuit as a third clock signal.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: June 26, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinichiro Shiratake, Yukihito Oowaki, Fumitoshi Hatori, Mototsugu Hamada, Hiroyuki Hara
  • Patent number: 7233186
    Abstract: A clock generation circuit receives a reference clock signal for outputting clock signals to peripheral circuits. A duty ratio of at least one of output buffer signals output from buffer circuits included in the clock generation circuit is varied so that a duty ratio of at least one of the clock signals can be varied.
    Type: Grant
    Filed: October 10, 2003
    Date of Patent: June 19, 2007
    Assignee: Renesas Technology Corp.
    Inventor: Koichi Ishimi
  • Patent number: 7180353
    Abstract: A clock distribution apparatus for providing a local clock signal having a first voltage swing to a circuit unit being on a same substrate includes a global clock distribution network for generating and distributing a global clock signal having a second voltage swing being less than the first voltage swing; and a local clock converting unit being electrically connected between the global clock distribution network and the circuit unit. The local clock converting unit includes a level shifter for converting the global clock signal into the local clock signal.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: February 20, 2007
    Assignee: Mediatek Incorporation
    Inventors: You-Ming Chiu, Yung-Chieh Yu
  • Patent number: 7170332
    Abstract: Reference signal generators are provided that automatically adjusts a reference signal's amplitude when that signal is delivered into system loads having unknown capacitances. The amplitude is preferably initiated at a maximum amplitude to insure operation of system elements that require the reference signal. It is subsequently adjusted downward to a controlled reference amplitude which is predetermined to be an amplitude sufficient to sustain proper operation of the system elements but sufficiently reduced to minimize the spurious signals typically generated by fast high-level current transitions. In addition, the reduction to the controlled amplitude reduces the system current drain. The level control is realized in a buffer amplifier so that the amplitude level of an oscillator signal can be set independently to maximize its signal-to-noise performance. Accordingly, requirements for the reference amplitude do not compromise requirements for the amplitude level of the oscillator signal.
    Type: Grant
    Filed: April 15, 2004
    Date of Patent: January 30, 2007
    Assignee: Analog Devices, Inc.
    Inventors: Marc E. Goldfarb, Edmund J. Balboni
  • Patent number: 7161400
    Abstract: A circuit and method for synchronized clocking of components such as registers. Registers are clocked by individual component clock signals having the same frequency but potentially different phases due to differing propagation delays. Separate component clock signals are received by registers are brought into phase by evaluating the phases of the component clock signals at the registers, and synchronizing the component clock signal of each register to that of the previous register in a sequence.
    Type: Grant
    Filed: October 13, 2004
    Date of Patent: January 9, 2007
    Assignee: Rambus Inc.
    Inventors: Huy M. Nguyen, Benedict C. Lau, Leung Yu, Jade M. Kizer
  • Patent number: 7158441
    Abstract: A semiconductor integrated circuit in which multiphase clock signals having the same phase difference are supplied from a multi-stage differential ring oscillator to other circuits, the multiphase clock signals can be prevented from being degraded in waveform due to electrostatic coupling between wirings of the multiphase clock signals and also wired in as small an area as possible. The semiconductor integrated circuit includes: multiple stages of amplifier circuits, connected in a ring form, for performing oscillating operation; a logic circuit for performing logic operation on the basis of predetermined ones of output signals of the multiple stages of amplifier circuits to output a plurality of clock signals having different phases from each other and duties not equal to 0.5; and a plurality of wirings for transmitting the plurality of clock signals output from the logic circuit.
    Type: Grant
    Filed: December 13, 2004
    Date of Patent: January 2, 2007
    Assignee: Thine Electronics, Inc.
    Inventor: Junichi Okamura
  • Patent number: 7151398
    Abstract: Clock signal generators include an integrated circuit chip having a PLL-based or DLL-based clock driver therein. The clock driver is configured to support generation of a plurality of clock signals having different frequencies in a range between 1 and 1/N times a frequency of an internal clock signal and full-period programmable skew characteristic, where N is a positive integer greater than one. The clock driver also includes a divide-by-N clock generator that is configured to generate N divide-by-N clock signals that have the same frequency but are phase shifted relative to each other. This clock generator operates in response to a first skew signal having a frequency equal to the frequency of the internal clock signal. A one-of-N select circuit is provided. This select circuit is configured to select one of the N divide-by-N clock signals in response to a time unit position signal.
    Type: Grant
    Filed: September 1, 2005
    Date of Patent: December 19, 2006
    Assignee: Integrated Device Technology, Inc.
    Inventors: Shawn Giguere, Declan P. McDonagh, Roland Knaack, Bamdhamravuri S. Satishbabu
  • Patent number: 7151399
    Abstract: A technique for generating multiple clock signals using a frequency generator for generating a common clock signal. A first digital divider and multiplier receives the common clock signal and produces a first clock signal. A second digital divider and multiplier receives the common clock signal and produces a second clock signal, the second clock signal being at a different frequency than the first clock signal. A third digital divider and multiplier receives the common clock signal and produces a third clock signal, the third clock signal being at a different frequency than the first clock signal and the second clock signal. The common clock signal can be the greatest common measure of the first, second and third clock signals divided by a multiple of two.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: December 19, 2006
    Assignee: Toshiba America Electronic Components, Inc.
    Inventor: Masao Kaizuka
  • Patent number: 7135907
    Abstract: A differential sinusoidal signal pair is generated on an integrated circuit (IC). The differential sinusoidal signal pair is distributed to clock receiver circuits, which may be differential amplifiers. The clock receiver circuits receive the differential sinusoidal signal pair and convert the differential sinusoidal pair to local clock signals. Power consumption and noise generation are reduced as compared to conventional clock signal distribution arrangements.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: November 14, 2006
    Assignee: International Business Machines Corporation
    Inventors: Anthony Richard Bonaccio, John Maxwell Cohn, Alvar Antonio Dean, Amir H. Farrahi, David J. Hathaway, Sebastian Theodore Ventrone
  • Patent number: 7129765
    Abstract: A clock distribution network having: a main trunk configured to provide a differential clock signal; a plurality of branches coupled to the main trunk for distributing the differential clock signal to a plurality of circuit elements on the integrated circuit; and a plurality of switches coupling the main trunk to the plurality of branches.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: October 31, 2006
    Assignee: Xilinx, Inc.
    Inventors: Vasisht Mantra Vadi, Steven P. Young, Atul V. Ghia, Adebabay M. Bekele, Suresh M. Menon