Clocking, Delay Or Transmission Line Patents (Class 307/409)
  • Patent number: 11407312
    Abstract: A charging cable for a motor vehicle can be operated by electricity having a filter device. The charging cable includes a first conductor and a second conductor configured to transfer a current, a safety ground line, and a signal line configured to transfer charging information relating to a charging process. The filter device includes a core around which the first and second conductors and the safety ground line are wound, and the signal line is wound around the core.
    Type: Grant
    Filed: July 10, 2019
    Date of Patent: August 9, 2022
    Assignee: Bayerische Motoren Werke Aktiengesellschaft
    Inventors: Richard Bogenberger, Harald Ernst, Sergey Kochetov, Stephan Riess, Volker Zwillich
  • Patent number: 10756714
    Abstract: Disclosed aspects relate to a clock distribution network of a synchronous logic device. The synchronous logic device comprises multiple sub-circuits belonging to different clock domains. The clock distribution network comprises a clock source operable for providing a global clock signal, at least one programmable delay line associated with a certain sub-circuit operable for generating a local clock signal for said sub-circuit by delaying the global clock signal or a signal derived therefrom and a global skew control circuit for managing clock skew between the local clock signals. The global skew control circuit is operable for managing clock skew between at least some local clock signals by regularly adjusting the delay caused by at least one programmable delay line when in a deskewing operating mode, and disabling adjusting the delays of the programmable delay lines when in a locked operating mode.
    Type: Grant
    Filed: May 28, 2019
    Date of Patent: August 25, 2020
    Assignee: International Business Machines Corporation
    Inventors: Andreas Arp, Fatih Cilek, Michael Koch, Matthias Ringe
  • Patent number: 10348279
    Abstract: Disclosed aspects relate to a clock distribution network of a synchronous logic device. The synchronous logic device comprises multiple sub-circuits belonging to different clock domains. The clock distribution network comprises a clock source operable for providing a global clock signal, at least one programmable delay line associated with a certain sub-circuit operable for generating a local clock signal for said sub-circuit by delaying the global clock signal or a signal derived therefrom and a global skew control circuit for managing clock skew between the local clock signals. The global skew control circuit is operable for managing clock skew between at least some local clock signals by regularly adjusting the delay caused by at least one programmable delay line when in a deskewing operating mode, and disabling adjusting the delays of the programmable delay lines when in a locked operating mode.
    Type: Grant
    Filed: May 11, 2017
    Date of Patent: July 9, 2019
    Assignee: International Business Machines Corporation
    Inventors: Andreas Arp, Fatih Cilek, Michael Koch, Matthias Ringe
  • Patent number: 10298217
    Abstract: The disclosure relates to a skew control circuit for controlling the skew between at least three clock signals, the clock signals being forwarded to different clock domains associated with the respective clock signals. The skew control circuit comprises multiple programmable delay elements arranged within a signal flow before the respective clock domain, a skew detector arrangement operable for detecting skews between at least two pairs of the clock signals, and a control circuit operable for adjusting delays caused by the programmable delay elements. The control circuit is operable for carrying out a de-skewing operation. The de-skewing operation comprises determining an order of occurrence of edges of the signals, selecting one of the programmable delay elements based on the determined order, and adjusting the delay caused by the selected programmable delay element.
    Type: Grant
    Filed: July 14, 2017
    Date of Patent: May 21, 2019
    Assignee: International Business Machines Corporation
    Inventors: Michael V. Koch, Andreas H. A. Arp, Matthias Ringe, Fatih Cilek
  • Patent number: 9596074
    Abstract: Embodiments of the present invention provide improved techniques for recovering clock information from data signals. In one embodiment, a general purpose device such as a real-time oscilloscope acquires a data signal. The device takes a derivative of the data signal, then computes the square or absolute of the derivative before applying a bandpass filter. The bandpass filter is a windowing function a spectrum that is wider than the clock, and has a flat top and smooth transitions on both sides. In one embodiment, at Tukey window may be used. The device finds edge crossing times of the filtered result, and applies a phase-locked loop or lowpass filter to the edge crossing times in order to recover a stable clock signal. When the improved techniques are implemented in software, they may be used with any number of different equalizers that are required by various high-speed serial data link systems.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: March 14, 2017
    Assignee: Tektronix, Inc.
    Inventor: Kan Tan
  • Patent number: 8054266
    Abstract: A driving apparatus for a display device includes a gray voltage generator that generates a plurality of gray voltage sets, each including a plurality of gray voltages having different levels, and a signal converter that includes a first selector for selecting one gray voltage set among the plurality of gray voltage sets on the basis of a first portion of an image signal and a second selector for selecting one or more gray voltages among the plurality of gray voltages belonging to the selected gray voltage set on the basis of a second portion of the image signal to output and select gray voltages with a smaller size digital-analog converter.
    Type: Grant
    Filed: January 11, 2007
    Date of Patent: November 8, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Doo-Hyung Woo, Il-Gon Kim, Kee-Chan Park
  • Patent number: 8027389
    Abstract: A transmission circuit (101) for transmitting data onto a transmission line, and a mask circuit (102) for generating a mask signal (105) for removing a reflected wave based on a transmission timing notification signal (104) supplied form the transmission circuit (101) are provided. For example, a timer circuit (301) causes the mask signal (105) to be effective only for a predetermined time immediately after transmission. A logic circuit (302) is used to remove a reflected wave from the received signal (106) based on the mask signal (105), and a resultant masked received signal (107) is input to a reception circuit (103).
    Type: Grant
    Filed: December 6, 2006
    Date of Patent: September 27, 2011
    Assignee: Panasonic Corporation
    Inventors: Takeshi Kado, Hideo Imai
  • Patent number: 7627773
    Abstract: The invention provides a logic circuit to identify time difference between signals having a variation in delay, and an integrated circuit which can evaluate variations in delay among internal signals. By using a logic circuit which outputs different number of pulse depending on a relationship of delay when a first signal and a second signal which are a pair of digital signals having a time difference are inputted, variations in delay of internal signals of an integrated circuit can be evaluated. Specifically, an output signal is generated by a logical operation of values of the first signal and second signal in a period in which the first signal is High and the second signal is Low, and values of a first signal and a second signal immediately before them by using a latch circuit. Further, by using a delay circuit which can set a delay time of an input signal, time difference between signals can be evaluated quantitatively.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: December 1, 2009
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Kiyoshi Kato
  • Patent number: 7512033
    Abstract: An operation clock controller for preventing a semiconductor memory device from operating when an operation frequency of an external clock is higher than a predetermined frequency. The operation clock controller includes a clock buffer for buffering an external clock to output an internal clock; a unit delaying set for sequentially delaying the internal clock to output a plurality of delayed clocks; a phase detecting block for detecting logic levels of the delayed clocks at a rising edge of the internal clock to output phase detecting signals; a sampling pulse generator for outputting a sampling signal generated at a predetermined point of the internal clock; a latching block for outputting a phase detection latch signal by sampling and latching the phase detection signal at a point of the sampling signal being inputted; and a frequency detection block for outputting the frequency detection signal by logically combining the phase detection latch signal.
    Type: Grant
    Filed: November 13, 2007
    Date of Patent: March 31, 2009
    Assignee: Hynix Semiconductor Inc.
    Inventors: Hwang Hur, Jun-Gi Choi
  • Patent number: 7352826
    Abstract: An analog delay circuit to impart a group delay to an analog input signal is described. The analog delay circuit may comprise a capacitor to impart at least a portion of the group delay to the analog output signal and a buffer circuit coupled between the capacitor and an input stage to substantially remove at least a portion of a capacitive load at the input stage.
    Type: Grant
    Filed: December 19, 2003
    Date of Patent: April 1, 2008
    Assignee: Intel Corporation
    Inventor: Anush A. Krishnaswami
  • Patent number: 7103274
    Abstract: An apparatus having n-number of working cross-connects for cross-connecting an n-bit input signals arriving from a plurality of input paths on a per-bit basis; n-number of first logic circuits for calculating the exclusive-ORs of each said n-bit and applying outputs to a standby cross-connect for providing outputs; n-number of second logic circuits for calculating the exclusive-ORs of said output signals from each of said working cross-connects and from the single standby cross-connect; and third logic circuits for selecting output signals of said working cross-connects and outputs of the second logic circuits. The apparatus detects the occurrence of an abnormality in working cross-connects by monitoring the outputs of the second logic circuits, identifies the faulty cross-connect by successively turning off one of the n-inputs to the first and second logic circuits, and select outputs from the second logic circuits instead of from the faulty cross-connect by using the third logic circuits.
    Type: Grant
    Filed: August 5, 2003
    Date of Patent: September 5, 2006
    Assignee: Fujitsu Limited
    Inventors: Kazuhiro Kunimatsu, Hiroya Egoshi, Akio Takayasu, Yukiko Miyazaki
  • Patent number: 7020794
    Abstract: An interleaved delay line for use in phase locked and delay locked loops is comprised of a first portion providing a variable amount of delay substantially independently of process, temperature and voltage (PVT) variations while a second portion, in series with the first portion, provides a variable amount of delay that substantially tracks changes in process, temperature, and voltage variations. By combining, or interleaving, the two types of delay, single and dual locked loops constructed using the present invention achieve a desired jitter performance under PVT variations, dynamically track the delay variations of one coarse tap without a large number of delay taps, and provide for quick and tight locking. Methods of operating delay lines and locked loops are also disclosed.
    Type: Grant
    Filed: March 14, 2005
    Date of Patent: March 28, 2006
    Assignee: Micron Technology, Inc.
    Inventor: Feng Lin
  • Patent number: 7015600
    Abstract: A pulse generator circuit is disclosed including a delay element coupled to a logic circuit. The delay element receives a clock signal CLK and a signal X and produces a signal XN dependent upon the clock signal CLK and the signal X. The logic circuit receives the clock signal CLK and the signal XN and produces a signal ACLK such that ACLK=CLK·XN?. The signal ACLK may include a series of positive pulses. The delay element may be, for example, one of multiple delay elements coupled in series, and signal X may be an output of a preceding one of the delay elements. A semiconductor device is described including the above pulse generator circuit and a self-resetting logic circuit. The self-resetting logic circuit receives the signal ACLK and one or more input signals and performs a logic operation using the one or more input signals during the positive pulses.
    Type: Grant
    Filed: October 10, 2002
    Date of Patent: March 21, 2006
    Assignee: International Business Machines Corporation
    Inventors: Chad Allen Adams, Todd Alan Christensen, Peter Thomas Freiburger
  • Patent number: 6889349
    Abstract: A method and circuit periodically pseudo-randomly select a sample of digital event pulses comprising a logic data signal. A first timer times a first time interval. A second timer times a second time interval within the first time interval. A delay timer, coupled between the first and second timers, pseudo-randomly delays initiation of the second timer from the start of the first time interval. In one embodiment, the first timer is an (N+1)-bit binary counter. The delay timer includes an N-bit round robin latch and seeded by a pseudo-random number generator having fewer than N bits, the round robin latch shifting its contents to form an N-bit pseudo-random number. The second timer is initiated when the value of the first timer is equivalent to the round robin latch. A coincidence circuit passes digital event pulses during the second time interval. A count is accumulated of the sampled digital event pulses.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: May 3, 2005
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Joseph Weiyeh Ku
  • Patent number: 6868504
    Abstract: An interleaved delay line for use in phase locked and delay locked loops is comprised of a first portion providing a variable amount of delay substantially independently of process, temperature and voltage (PVT) variations while a second portion, in series with the first portion, provides a variable amount of delay that substantially tracks changes in process, temperature, and voltage variations. By combining, or interleaving, the two types of delay, single and dual locked loops constructed using the present invention achieve a desired jitter performance under PVT variations, dynamically track the delay variations of one coarse tap without a large number of delay taps, and provide for quick and tight locking. Methods of operating delay lines and locked loops are also disclosed.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: March 15, 2005
    Assignee: Micron Technology, Inc.
    Inventor: Feng Lin
  • Patent number: 6091165
    Abstract: A method and an apparatus reduce peak electro-magnetic (EM) emissions from power and ground planes in, for example, a printed circuit board (PCB) by phase shifting synchronous signal sources to distribute EM emissions over a frequency range and by canceling at least some EM emissions with an inverse signal. According to one aspect of the present invention, two signal sources provide periodic outputs having the same period. The output of one of the signal sources, however, is delayed with respect to the output of the other signal source. Each signal source is coupled to a signal trace. The propagation delay over the signal trace coupled to the delayed signal source is shorter than the propagation delay over the other signal trace by the amount of the delay between the respective output signals. According to another aspect of the present invention, a noise cancellation driver is coupled to a signal source, a power or ground plane of the signal source, and an inverse voltage plane.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: July 18, 2000
    Assignee: Intel Corporation
    Inventors: Raymond P. Askew, Jeffrey W. Day
  • Patent number: 5537655
    Abstract: A synchronizing circuit comprises a plurality of substantially identical modules for receiving respective asynchronous input signals and respective local clock signals with the local clock signals of the respective modules being substantially synchronized. Each module of the synchronizing circuit comprises a de-metastabilizer stage, a global synchronizing stage and a majority edge detector and voter network. The de-metastabilizer stage receives the input signal of the module and provides an output signal free of glitches and metastable conditions, synchronized to the local clock signal. The global synchronizing stage receives the output signals of the de-metastabilizer stage of each module and provides respective output signals synchronized to the local clock signal. The majority edge detector and voter network receives the output signals of the global synchronizing stage and outputs a voted output signal synchronized to the other modules' voted output signals and to the local clock signal.
    Type: Grant
    Filed: November 21, 1994
    Date of Patent: July 16, 1996
    Assignee: The Boeing Company
    Inventor: Tuong K. Truong
  • Patent number: 5471488
    Abstract: An apparatus for transferring data between a main processor and its memory and a packet switch includes a first bus coupled to the main processor and its memory, a bidirectional first-in-first-out (FIFO) buffer coupled between the first bus and a second bus, and having a first port connected to the first bus and a second port connected to the second bus, a communications processor, coupled to the second bus, a memory operatively coupled to the second bus, a first direct memory access (DMA) engine coupled between the first bus and the FIFO buffer for transferring data between the main processor and the FIFO buffer, a second direct memory access (DMA) engine coupled between the FIFO buffer and the second bus for transferring data between the FIFO buffer and the second bus, and a packet switch interface, operatively coupled between the second bus and the switch, for interfacing the second bus to the switch, wherein packets are communicated between the memory of the main processor and the switch in accordance wit
    Type: Grant
    Filed: April 5, 1994
    Date of Patent: November 28, 1995
    Assignee: International Business Machines Corporation
    Inventor: Carl A. Bender
  • Patent number: 5465347
    Abstract: A circuit to provide single phase clock signals having controlled clock skew to multiple integrated circuit chips is described. A source of single phase clock signals is supplied to a clock signal distribution tree of each integrated circuit. Phase comparison of signals produced by each clock distribution circuit tree provides a control signal for controlling the delay of a clock signal applied to a respective clock distribution tree. A gating circuit is disclosed which produces, in response to each clock signal produced by the clock distribution trees, an accurately controlled LOAD ENABLE and OUTPUT ENABLE signal.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: November 7, 1995
    Assignee: International Business Machines Corporation
    Inventors: Hu H. Chao, Jung H. Chang, Feng-Hsien W. Shih
  • Patent number: 5440592
    Abstract: A delay chain having a known number of delay elements providing various delayed outputs of its input, a first and a second register set, and preferably, an array of multiplexors, are provided to measure the frequency of a digital signal, and the high and low time of its period. The digital signal to be measured is provided to the delay chain as input. A first and a second sample of the various delayed outputs are taken at the beginning and the end of a known time period, and stored in the first and second registers, one delayed output per register bit. The sample results stored in the register sets are read out through the multiplexors, and used to determine the frequency of the digital signal being measured, and the high and low time of its period.
    Type: Grant
    Filed: March 31, 1993
    Date of Patent: August 8, 1995
    Assignee: Intel Corporation
    Inventors: David Ellis, Gary Brady
  • Patent number: 5428764
    Abstract: A radial clock distribution system that converts a standard bus clock signal into two pairs of inverted and non-inverted clocking signals. The two pairs of clocking signals have a lower frequency, have a different phase, and are shifted one clock period apart. The clocking signals are transferred over a first set of signal lines of equal length and impedance to computing systems components that are connected to a synchronous bus. Each component includes at least one clock repeater chip to convert the clocking signals (e.g., change these signals to a 5 volt CMOS level) to a different format. The converted clocking signals are then transferred over a second set of signal lines of equal length and impedance to the gate arrays. The gate arrays includes direct drive circuitry that receives the converted clocking signals and transmits these signals to internal driver circuitry. These signals are transferred over low skew lines.
    Type: Grant
    Filed: April 24, 1992
    Date of Patent: June 27, 1995
    Assignee: Digital Equipment Corporation
    Inventor: Barry A. Maskas
  • Patent number: 5369640
    Abstract: A remote delay regulator circuit measures the effects of intrinsic propagation delays experienced by a system clock signal propagating through an extended clock distribution path that encompasses a clock repeater chip, a module transmission network and a clock distribution network of an integrated circuit (IC) chip associated with a clock repeater chip. Circuits of the remote delay regulator are contained on the repeater chip and on the associated IC chip. Delay measurement of the remote IC clock distribution network is provided by sensing the clock signal at the beginning of the network using a BEFORE sense tap and at the end of the network using an AFTER sense tap. The BEFORE and AFTER sense taps are routed to a signal generation circuit on the repeater chip where measurement signals are generated that define the beginning and end of a measurement cycle.
    Type: Grant
    Filed: April 16, 1993
    Date of Patent: November 29, 1994
    Assignee: Digital Equipment Corporation
    Inventors: Richard B. Watson, Russell Iknaian, Hansel A. Collins
  • Patent number: 5347184
    Abstract: Two separate receivers (120,122) receive the input signal (128) and the clock signal (126). During the inactive state of the clock signal, the first receiver produces a low state output (130) and the second receiver produces a high state output (132). Both outputs feed combinational logic (124), which produces two outputs (142,144) both normally low. Upon transition of the clock signal, the output of only one of the receivers changes state to match the logic state of the input signal. The output of the other receiver maintains its logic state. Upon the change in the clock signal, only one of the combinational logic outputs changes state to a logical high state to indicate the state of the one input signal.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: September 13, 1994
    Assignee: Texas Instruments Incorporated
    Inventors: Michael C. Stephens, Jr., Roger D. Norwood, Duy-Loan T. Le, Kenneth A. Poteet
  • Patent number: 5184210
    Abstract: An arrangement for interconnecting high density signals of integrated circuits includes an electronic circuit on a multilayered substrate which includes at least three layers. These layers comprise a signal layer for carrying signals in the electronic circuit, a dielectric layer of organic material disposed adjacent the signal layer, and a metallic reference layer. The layers are disposed such that the dielectric layer is between the signal layer and the metallic reference layer. For providing controlled line impedance and for reducing cross-talk between the signals carried in the electronic circuit, the metallic reference layer includes uniformly spaced apertures which are situated in a slanted grid arrangement.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: February 2, 1993
    Assignee: Digital Equipment Corporation
    Inventor: Scott R. Westbrook
  • Patent number: 5078464
    Abstract: An optical logic device based on the time-shift-keying architecture is described in which digital logic functions are realized by applying appropriate signal pulses to a nonlinear shift or "chirp" element whose output is supplied to a dispersive element capable of supporting soliton propagation. In an optical fiber realization of the optical logic device, two orthogonally polarized pulses are supplied to the combination of a moderately birefringent fiber acting as the nonlinear chirp element and a polarization maintaining fiber acting as the soliton dispersive delay element having a anomolous group velocity dispersion at the signal wavelengths of interest. A nonlinear frequency shift is created in one of the pulses in the former element through cross-phase modulation and, in turn, the frequency shift is translated into a temporal shift of the affected pulse in the latter element. These devices operate at switching energies approaching 1pJ.
    Type: Grant
    Filed: November 7, 1990
    Date of Patent: January 7, 1992
    Assignee: AT&T Bell Laboratories
    Inventor: Mohammed N. Islam
  • Patent number: 5070787
    Abstract: The invention provides an explosively actuated switch and a method of using the same. The switch will include primary conductive elements which will remain generally stationary, and one or more movable conductive elements which will be clamped between the stationary elements. Various types of mechanisms may be utilized to exert a clamping force on one or more of the stationary members. An explosive material is provided to move the movable members from engagement with the stationary members upon detonation.
    Type: Grant
    Filed: June 24, 1988
    Date of Patent: December 10, 1991
    Assignee: The Board of Regents of the University of Texas System
    Inventors: William F. Weldon, Ben M. Rech, Robert L. Sledge
  • Patent number: 5024499
    Abstract: An optical AND gate for use in a cross-bar arithmetic/logic unit including first and second optical substrates which are configured adjacent to one another with each of the optical substrates having a respective plurality of optical paths formed thereon. The pattern of optical paths form a plurality of intersecting regions where the optical paths associated with one of the optical substrates overlaps the optical paths associated with the other optical substrate. The optical substrates are operable for transmitting an incident light beam there through so as to produce an output at one of the intersecting regions. The optical substrates transmit the incident light beam only through the optical paths which have been illuminated by a plurality of light sources.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: June 18, 1991
    Assignee: The Boeing Company
    Inventor: R. A. Falk
  • Patent number: 4973122
    Abstract: An optical device includes a 50-50 cross-coupler having a pair of ports optically coupled by a waveguide which includes a portion of material having a non-linear refractive index with a relaxation time such that the effect on the non-linear portion of a first pulse passing through the portion last long enough to affect the phase of a second pulse relative to the first. It finds application as a logic element, optical amplifier modulator and the like.
    Type: Grant
    Filed: August 2, 1989
    Date of Patent: November 27, 1990
    Assignee: British Telecommunications public limited company
    Inventors: David Cotter, Nicholas J. Doran, Keith J. Blow, David C. Wood
  • Patent number: 4964687
    Abstract: An optical latch includes first and second optical switches arranged in series. An input signal is received in the first optical switch and is passed through to the second optical switch. The second optical switch latches-up to this received signal. Then the first optical switch is disabled to isolate the second optical switch from inputs to the first optical switch. Feedback lines from the output of the second optical switch to the input of the second optical switch ensure that the second optical switch remains latched. Switching signals are provided at appropriate timing to ensure correct operation of the optical latch.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: October 23, 1990
    Assignee: The Boeing Company
    Inventor: R. Aaron Falk
  • Patent number: 4961621
    Abstract: An optical parallel-to-serial converter constructed from at least two optical shift registers coupled in cascade by an optical two-to-one combiner. The input port of the first optical shift register serves as one input to the parallel-to-serial converter, an extra optical combiner optically coupled to the last of said optical shift registers serves as one input port, while the optical combiners coupling said optical shift registers serve as the other input ports receiving parallel optical pulses. The output port of the last of said cascaded optical shift registers serves as the output port of the parallel-to-serial converter. The shift registers are controlled by two clocks, operating at the same rate, but each out of phase with the other, providing control signals to shift and output said optical pulses serially from said shift registers to effect a parallel-to-serial conversion.
    Type: Grant
    Filed: December 22, 1988
    Date of Patent: October 9, 1990
    Assignee: GTE Laboratories, Inc.
    Inventor: Shing-Fong Su
  • Patent number: 4923267
    Abstract: An optical shift register constructed from at least two optical memory cells connected in cascade, each memory cell having an optical combiner, a 1.times.2 optical switch, a clock, and an optical amplifier, all connected by optical fibers. Each memory cell in the sequence is connected to the next sequential cell by an optical fiber from its output port to the input port of the next sequential cell. The input port of the first optical memory cell serves as the input to the shift register. The output port of the last sequential optical memory cell serves as the output port of the shift register. Each cell is controlled by a clock, all clocks operating at the same rate, but each out of phase with the clock in the next sequential cell. Control signals are provided by said clocks to shift optical pulses from one cell to the next for the enter-shift-exit cycle of the shift register.
    Type: Grant
    Filed: December 5, 1988
    Date of Patent: May 8, 1990
    Assignee: GTE Laboratories Incorporated
    Inventor: Shing-Fong Su
  • Patent number: 4877974
    Abstract: A clock generator which is cascade connected a plurality of single-phase pulse generator circuits including RS flip-flops and delay circuits for defining the pulse width of one output at the RS flip-flop through gates controlling propagation of the other output of the RS flip-flop, so that the final clock frequency is variable by switching control of each gate, whereby a pulse width of each single-phase clock is defined by a delay duration of a delay circuit, thereby not depending on wave forms of the external clock and also the gates connected between the respective single-phase pulse generating circuits are switching-controlled to enable the frequency of the output clock to be variable.
    Type: Grant
    Filed: May 3, 1988
    Date of Patent: October 31, 1989
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroyuki Kawai, Shinichi Nakagawa
  • Patent number: 4713621
    Abstract: A phase synchronization circuit for controlling a graphic display device in a teletext receiving system. The phase synchronization circuit includes a delay circuit, adapted to delay in sequence clock signals which are to be phase-synchronized with a reference signal and to produce in sequence delayed clock signals, and a selection circuit, including set/reset circuits and gates, each gate receiving the output of the set/reset circuits and of the delayed clock signals. Among the delay clock signals, the signal that has the nearest edge timing to the edge of external signals is selected. The phase synchronization circuit has a short pull-in time and high-speed synchronization, is suitable for circuit integration, and offers improved reliability.
    Type: Grant
    Filed: March 28, 1985
    Date of Patent: December 15, 1987
    Assignee: Fujitsu Limited
    Inventors: Haruhiko Nakamura, Junya Tempaku
  • Patent number: 4463440
    Abstract: A system clock generator for use in a CMOS LSI chip includes a clock control signal generator for developing a control signal in response to a clock generating instruction or inhibition instruction; and a clock generator supplied with the output of an oscillator for developing a basic clock of a desired waveform for supply to the system, wherein the basic clock is developed or inhibited when the control signal is supplied from the clock control signal generator.
    Type: Grant
    Filed: April 15, 1981
    Date of Patent: July 31, 1984
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshikazu Nishiura, Takitsugu Mineyama, Kazuo Inoue
  • Patent number: 4390801
    Abstract: A circuit for reproducing a clock signal from digital signals reproduced from a recording medium makes self-clocking possible. The circuit includes a phase lock loop having a voltage-controlled oscillator that generates an oscillation output at a frequency which is approximately equal to or an integral multiple of the frequency of the clock signal contained in the reproduced signal. A pulse generating device outputs pulses of a fixed amplitude, triggered by the leading or trailing edge of the input signal, to the phase lock loop. An oscillation device outputs pulses having approximately the same period as the clock signal period. The oscillation device is triggered by the leading or trailing edge of the input signal. A selecting device gates the output pulses of the oscillation device to the phase lock loop.
    Type: Grant
    Filed: June 2, 1982
    Date of Patent: June 28, 1983
    Assignee: Trio Kabushiki Kaisha
    Inventors: Hirotaka Kurata, Shiro Yoshida