With Counter Patents (Class 327/265)
  • Patent number: 11139802
    Abstract: A ring oscillator is disclosed according to certain aspects of the present disclosure. The ring oscillator include N flip-flops, each of the N flip-flops having a data input, a clock input, and an output, wherein N is an integer greater than 1. In certain aspects, the output of each of the N flip-flops is coupled to the clock input of an adjacent other one of the N flip-flops, the output of each of the N flip-flops is coupled to a reset input or a preset input of a non-adjacent other one of the N flip-flops, and the data input of each of the N flip-flops is coupled to a voltage line or a ground line.
    Type: Grant
    Filed: July 15, 2020
    Date of Patent: October 5, 2021
    Assignee: QUALCOMM INCORPORATED
    Inventors: Percy Tehmul Marfatia, David Kidd
  • Patent number: 11079994
    Abstract: A technique capable of reducing wiring is provided. The mounting apparatus includes a display input device capable of displaying an image of multiple selection items for controlling the operation of the mounting apparatus and for inputting commands for selecting any selection item from the multiple displayed selection items, a control device, and a single cable connecting the display input device and the control device. When a command for selecting the selection item is inputted, the display input device transmits a command signal corresponding to the inputted command to the control device via the cable. In addition to transmitting a video signal for displaying the multiple selection items to the display input device via the cable, the control device updates the video signal based on the command signal received from the display input device and transmits the updated video signal to the display input device.
    Type: Grant
    Filed: November 29, 2016
    Date of Patent: August 3, 2021
    Assignee: FUJI CORPORATION
    Inventor: Hidenori Niwa
  • Patent number: 10734999
    Abstract: The present disclosure generally relates to semiconductor structures and, more particularly, to measurement circuits for logic paths and methods of manufacture. The circuit includes: a flip flop device outputting an output signal comprising an intrinsic delay; a logic path looping the output signal back to the flip flop device such that the intrinsic delay is to be received by the flip flop device; and an oscillator which feeds an input signal into the logic path and sweeps the input signal to alter the looped output signal thereby providing a maximum frequency of the logic path.
    Type: Grant
    Filed: June 3, 2019
    Date of Patent: August 4, 2020
    Assignee: GLOBALFOUNDRIES INC.
    Inventor: Kenta Yamada
  • Patent number: 9685125
    Abstract: An apparatus and method of driving data of a liquid crystal display device is disclosed, which can minimize an electromagnetic interference EMI noise by decreasing an output peak current of a data driver, the apparatus comprising a timing controller for supplying a reference source output enable signal; a delay circuit for delaying the reference source output enable signal and supplying a plurality of source output enable signals provided with the different delay times; and a data driver, including a plurality of data ICs to divide and drive data lines of a liquid crystal panel into a plurality of data blocks, for dispersing data output timing of the plurality of data ICs in response to the plurality of source output enable signals.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: June 20, 2017
    Assignee: LG DISPLAY CO., LTD.
    Inventors: Sung Chul Ha, Chang Hun Cho, Jin Cheol Hong
  • Patent number: 9030244
    Abstract: An integrated circuit includes a duty cycle detection circuit, a comparator circuit, and a tuning circuit. The duty cycle detection circuit receives a clock signal, such as a system clock signal, and detects the level of duty cycle distortion in the clock signal. The comparator circuit then generates an output based on the level of duty cycle distortion that is detected in the clock signal. The tuning circuit may accordingly adjust the clock signal based on the output generated by the comparator circuit to produce an adjusted clock output signal. As an example, the clock output signal produced by the tuning circuit after the adjustment may have a 50% (or significantly close to 50%) duty cycle.
    Type: Grant
    Filed: January 15, 2014
    Date of Patent: May 12, 2015
    Assignee: Altera Corporation
    Inventors: Mei Luo, Allen K. Chan, Thungoc M. Tran
  • Patent number: 8786347
    Abstract: In an embodiment, a delay circuit includes a ring oscillator circuit and a counter circuit. The ring oscillator circuit includes a delay chain having delay elements and configured to generate one of more clock cycles of an oscillator clock signal in response to a clock cycle of a clock signal. The counter circuit includes two counters that are configured to store a count state corresponding to a number of clock cycles of the oscillator clock signal during a single clock cycle of the clock signal. A first buffer is configured to store the number of clock cycles of the oscillator clock signal. The delay circuit includes a buffer to store a bit pattern corresponding to a number of delay elements traversed in a partial clock cycle of the oscillator clock signal in response to the clock cycle of the clock signal based on outputs of the plurality of delay elements.
    Type: Grant
    Filed: May 14, 2013
    Date of Patent: July 22, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: Abhishek Chakraborty, Nagalinga Swamy Basayya Aremallapur, Vikas Narang
  • Patent number: 8724677
    Abstract: Provided are a method and apparatus (receiver) of receiving and processing a radio signal in a transmitter-receiver environment. The radio signals are transmitted across a wireless interface using Ultra Wideband (UWB) pulses. A transmitted reference approach is utilized. The radio signal include pairs of UWB pulses with each pair of pulses separated by a fixed time delay. The two pulses are then combined to provide for improved noise immunity.
    Type: Grant
    Filed: October 17, 2013
    Date of Patent: May 13, 2014
    Assignee: University of South Florida
    Inventor: James L. Tucker
  • Patent number: 8588270
    Abstract: The invention includes a method for transmitting and detecting high speed Ultra Wideband pulses across a wireless interface. The transmitter includes a serializer and pulse generator. The receiver comprises a fixed delay line, multiplier, local serializer (with a sequence matching the transmitter), digital delay lines, low noise amplifier and logic fan-out buffer along with an array of D flip-flop pairs. Each flip-flop pair is enabled, at fixed time increments, to detect signals at a precise time; the timing is controlled by the pseudo-random sequence generated by the local serializer. A local tunable oscillator is controlled by detecting the phase change of the incoming signal and applying compensation to maintain the phase alignment and clock synchronization of the receiver to the clock reference of the transmitter. The invention uses a pair of pulses with a fixed delay and then relies on mixing the two to provide better noise immunity.
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: November 19, 2013
    Assignee: University of South Florida
    Inventor: James L. Tucker
  • Patent number: 8575983
    Abstract: A waveform generator has a waveform generation circuit storing waveform data for an analog waveform signals having dead time periods without the need for storing data on the dead time. A sequencer having a sequence memory stores sequence data that controls the sequencing of one or more signal components and associated dead times of the analog waveform signal. The timing of the dead time is controlled by a sampling clock and a wait time counter. The generation of the signal components is controlled by the sampling clock controlling the generation of addresses for a waveform memory storing digital data of the sampling components. The waveform memory digital data is converted to an analog waveform signal.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: November 5, 2013
    Assignee: Tektronix, Inc.
    Inventor: Ryoichi Sakai
  • Patent number: 8502587
    Abstract: This document discusses, among other things, a voltage regulator having a plurality of switching devices, coupled in parallel, and configured to selectively provide a variable available drive current using a comparison of a regulated Dc output voltage to at least one reference voltage.
    Type: Grant
    Filed: December 22, 2009
    Date of Patent: August 6, 2013
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Timothy Alan Dhuyvetter, Brian Ben North
  • Patent number: 8362932
    Abstract: Calibration data for calibrating time to digital conversion is obtained by switching a feed circuit of a time to digital converter between a normal operating mode or a calibration mode. A delay circuit with a delay circuit input and a plurality of taps outputs. A sampling register samples data from the data inputs. The feed circuit provides for selection of transitions of the oscillator signal that control timing of a first active transition at the clock circuit after a transition at the delay circuit input. A control circuit switches the feed circuit between normal operating mode and calibration mode, and controls the feed circuit successively to select a plurality of different transitions to control timing of the first active transition in the calibration mode. The control circuit reads out resulting data from the sampling register for each selection and determines calibration data for the oscillator signal from said data.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: January 29, 2013
    Assignee: ST-Ericsson SA
    Inventors: Nenad Pavlovic, Manel Collados Asensio, Xin He, Jan Van Sinderen
  • Patent number: 8250399
    Abstract: Aspects of the disclosure provide a network device. The network device includes a first port coupled to a first device to communicate with the first device, and a clock wander compensation module. The first port recovers a first clock based on first signals received from the first device. The clock wander compensation module includes a global counter configured to count system clock cycles based on a system clock of the network device, and a first port counter configured to count first clock cycles based on the recovered first clock. Further, the first port transmits a first pause frame to the first device based on the global counter and the first port counter.
    Type: Grant
    Filed: January 7, 2010
    Date of Patent: August 21, 2012
    Assignees: Marvell International Ltd., Marvell Israel (M.I.S.L.) Ltd.
    Inventors: Tal Mizrahi, Carmi Arad, Martin White, Tsahi Daniel
  • Patent number: 8107577
    Abstract: The present invention is a noise tolerant communication protocol device and method where a clock signal input triggers an internal delay clock in an integrated circuit. Data is presented to an input pin and sampled prior to the next external clock pulse based on the internal delay clock. A data pulse value is distinguished by input signal voltage level and not by pulse length. Sampling of data bits is deferred until a signal level is most likely stable, thereby avoiding sampling during periods around edges of changing data values. Therefore, error detection and correction circuitry is not required. A time reference pulse, produced by a bus master, is measured by the protocol device to determine a data transmission rate by the master. The timing of sampling of input signaling from the master is determined by the protocol device from measurement of the time reference pulse magnitude.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: January 31, 2012
    Assignee: Atmel Corporation
    Inventor: Philip S Ng
  • Patent number: 8048732
    Abstract: An apparatus and method of manufacture for metal-oxide semiconductor (MOS) transistors is disclosed. Devices in accordance with the invention are operable at voltages below 2V. The devices are area efficient, have improved drive strength, and have reduced leakage current. A dynamic threshold voltage control scheme comprised of a forward biased diode in parallel with a capacitor is used, implemented without changing the existing MOS technology process. This scheme controls the threshold voltage of each transistor. In the OFF state, the magnitude of the threshold voltage of the transistor increases, keeping the transistor leakage to a minimum. In the ON state, the magnitude of the threshold voltage decreases, resulting in increased drive strength. The invention is particularly useful in MOS technology for both bulk and silicon on insulator (SOI) CMOS. The use of reverse biasing of the well, in conjunction with the above construct to further decrease leakage in a MOS transistor, is also shown.
    Type: Grant
    Filed: February 8, 2010
    Date of Patent: November 1, 2011
    Assignee: Semi Solutions, LLC
    Inventors: Ashok Kumar Kapoor, Robert Strain, Reuven Marko
  • Patent number: 7911250
    Abstract: A delay circuit includes a ring oscillator and a control circuit. The control circuit includes an edge detector that outputs a first control signal in response to a rising edge or a falling edge of an input signal, and a counter that counts the number of pulses of an output pulse signal output from the ring oscillator and outputs a second control signal upon reaching a predetermined count number. The control circuit performs control to make the ring oscillator oscillate in response to the first control signal and to output the input signal in response to the second control signal.
    Type: Grant
    Filed: November 30, 2009
    Date of Patent: March 22, 2011
    Assignee: RENESAS Electronics Corporation
    Inventor: Junya Okubo
  • Publication number: 20100295590
    Abstract: A time to digital converter includes: a delay circuit having a plurality of delay stages that delay an input clock signal in multiple stages, at least one of the delay stages being a variable delay stage; a plurality of flip flops that capture outputs of the delay stages corresponding thereto in a one-to-one relation in response to input of a reference signal; an edge detecting circuit that detects changing edges of respective outputs of the flip flops; a counter circuit that counts a number of edges detected by the edge detecting circuit; and a control circuit that controls a delay amount of the variable delay stage according to the number of edges counted by the counter circuit.
    Type: Application
    Filed: March 10, 2010
    Publication date: November 25, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki Yoshihara, Hiroyuki Kobayashi
  • Patent number: 7777544
    Abstract: A method comprises applying a first delay to a first signal that is ahead of a second signal in a series of signals and determining a first number of delay units that provides the first delay to change an order between the delayed first signal and the second signal that has a phase difference with the first signal. The method further comprises determining a similar number for any other pair of signals in the series of signals that have the phase difference. The method further comprises determining a maximum and a minimum from the obtained numbers and determining linearity of the seriels of signals based on a difference between the maximum and the minimum.
    Type: Grant
    Filed: March 31, 2008
    Date of Patent: August 17, 2010
    Assignee: Intel Corporation
    Inventor: Bin Xue
  • Patent number: 7737750
    Abstract: A trimming system for determining a trim solution for a semiconductor device includes an internal value generating circuit for generating an internal value based upon a counter value. The relationship between the internal delay value and an external reference is compared to determine if the counter value is a possible trim solution, while predetermined counter values are excluded as a trim solution.
    Type: Grant
    Filed: January 16, 2007
    Date of Patent: June 15, 2010
    Assignee: Infineon Technologies AG
    Inventor: Steffen Loeffler
  • Patent number: 7728642
    Abstract: A programmable delay line includes a first oscillator that is enabled and generates a plurality of clock cycles of a clock signal in response to a transition of the input signal. A first programmable ripple counter is coupled to the first oscillator, counts with each successive clock cycle to a programmed count, and generates a first signal in response to reaching the programmed count. A control circuit is coupled to the first oscillator and to the first programmable ripple counter. The control circuit transitions the output signal and disables the first oscillator in response to the first signal.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: June 1, 2010
    Assignee: Xilinx, Inc.
    Inventor: John G. O'Dwyer
  • Patent number: 7665004
    Abstract: A timing generator that needs no analog circuit for adding jitters and allows the circuit scale and power consumption to be reduced.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: February 16, 2010
    Assignee: Advantest Corporation
    Inventors: Masakatsu Suda, Masahiro Ishida, Daisuke Watanabe
  • Patent number: 7646230
    Abstract: Certain exemplary embodiments can provide a system, which can comprise a circuit adapted to cause an actuation of an output device according to a control output. The control output can be generated comprising a control signal, the control signal extracted from a sequence of clock pulses. The sequence of clock pulses can comprise the control signal.
    Type: Grant
    Filed: September 5, 2008
    Date of Patent: January 12, 2010
    Assignee: Siemens Industry, Inc.
    Inventor: Steven Perry Parfitt
  • Patent number: 7609103
    Abstract: A delay circuit to generate and output a delayed signal delayed from an input signal includes a reference pulse generating circuit to generate a reference pulse train in response to the input of the input signal, the reference pulse generating circuit having a feedback circuit containing a delay portion to determine a time interval between the reference pulses, a counter to output count signals based on a reference clock, the counter receiving the reference pulse train generated by the reference pulse generating circuit as the reference clock, and a delayed signal output circuit to generate and output the delayed signal based on the input signal and the count signals.
    Type: Grant
    Filed: June 4, 2008
    Date of Patent: October 27, 2009
    Assignee: NEC Electronics Corporation
    Inventor: Toshiaki Motoyui
  • Patent number: 7587541
    Abstract: A master-slave device communication circuit includes a master device, a bus, and a slave device having a bus switch connected to the master device via the bus, and a status detecting circuit. The status detecting circuit includes a power input terminal and a detecting signal output terminal. A power terminal of the master device is connected to the power input terminal of the status detecting circuit. The detecting signal output terminal is connected to the bus switch and a trigger pin of the master device. When the master device supplies power to the slave device via the power terminal thereof, the detecting signal output terminal transmits a control signal to control the bus switch to turn on the bus and trigger the master device to communicate with the slave device after a delay time.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: September 8, 2009
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Yang-Yuan Chen, Ming-Chih Hsieh
  • Patent number: 7586351
    Abstract: An apparatus, includes a counter which counts a frequency of input of a first signal, a delay controller which generates a second signal by adding a delay to the first signal, the delay corresponding to the frequency, and a control circuit which halts the counter counting the frequency, when a phase difference between the first signal and the second signal is a predetermined value.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: September 8, 2009
    Assignee: NEC Corporation
    Inventor: Mutsumi Aoki
  • Patent number: 7583124
    Abstract: A delaying stage selecting circuit for selecting a specific delaying stage from a plurality of delaying stages, where the delaying stages are for outputting delayed clock signals, includes: a first register for sampling the delayed clock signals according to a clock signal to generate sampled values; first memory units, wherein the first memory units are utilized to memorize the sampled values, and each of first memory unit outputs at least one of the sampled values according to a corresponding first selecting signal; a first selecting unit, for outputting the sampled values according to a second selecting signal; a determining module, for determining if the sampled values meet a specific relation, where if the determination result is positive then determining the particular delaying stage; and a counter for generating a counting value to control the delayed clock signal sampled by the first register.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: September 1, 2009
    Assignee: Realtek Semiconductor Corp.
    Inventors: Tung-Chen Kuo, Ming-Chun Chang
  • Patent number: 7560968
    Abstract: An output driver capable of controlling a short circuit current includes a driving unit and a driving control unit. The driving unit receives a first driving signal and a second driving signal in response to a control signal and generates an output signal. The driving unit control unit includes a driving unit copying unit having the same construction as the driving unit and compares an output copying signal generated from the first and second driving signals by the driving unit copying unit with a reference voltage and generates the control signal that controls delays of the first and second driving signals in a test mode.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: July 14, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Dong-Jin Lee
  • Patent number: 7551015
    Abstract: An operating frequency generating method and circuit for a switching voltage converter are provided. The method includes the following steps. First, a reference clock signal and a digital period signal are received. The phase of the digital period signal is delayed according to at least one different delay time, so as to generate at least one delay period signal. The digital period signal or one of the delay period signals is selected as an operating frequency of the switching voltage converter at every predetermined time interval.
    Type: Grant
    Filed: October 23, 2006
    Date of Patent: June 23, 2009
    Assignee: Wisepal Technologies, Inc.
    Inventor: Yueh-Lin Yang
  • Patent number: 7535278
    Abstract: A clock manager circuit includes a number of clock output blocks, each providing an independent output. Counter controlled delay devices (CCDs) are used in these clock output blocks. To achieve full cycle delays, the CCDs are placed in parallel with outputs of the CCD outputs driving set and reset terminals of a common latch. The parallel connection of the CCDs, as opposed to a series connection, offers an increase in maximum frequency and possibly fewer needed CCDs than if the CCDs are placed in series. In one embodiment, at least one of the CCDs includes a counter/compare circuit with a frequency divider enabling the frequency of the CCD to be varied relative to the common input clock.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: May 19, 2009
    Assignee: Xilinx, Inc.
    Inventors: Robert M. Ondris, Raymond C. Pang, Kwansuhk Oh
  • Patent number: 7495495
    Abstract: When certain digital circuit devices receive data bus signals, I/O interfaces need to sample the data signals during a time when these signals are both valid and stable. Typically, the data signals are sampled at a time corresponding to a point halfway between rising and falling edges of a reference clock signal associated with the data bus, which sampling time corresponds to a 90-degree phase shift of the reference clock signal. In one embodiment of the invention, a delay count generator determines a delay value corresponding to a quarter cycle (i.e., 90 degrees) of the reference clock signal. In making this determination, a counter counts the number of clock cycles of an internally generated, relatively high-frequency clock signal, where the number corresponds to a specified portion (e.g., one half) of a period of a divided-down version of the reference clock signal. That number can then be used to generate the 90-degree delay value.
    Type: Grant
    Filed: November 17, 2005
    Date of Patent: February 24, 2009
    Assignee: Lattice Semiconductor Corporation
    Inventors: Fulong Zhang, Harold D. Scholz
  • Patent number: 7425858
    Abstract: A delay line is periodically configured into a delay-locked loop for calibration purposes. That is, the delay line is operated in an open loop mode during a first time period in which a signal, such as an aperiodic signal, is the input signal into the delay line. Periodically, the delay line is configured into a delay-locked loop and the delay line is recalibrated based on a periodic signal supplied to the delay-locked loop.
    Type: Grant
    Filed: January 6, 2006
    Date of Patent: September 16, 2008
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Anand Daga
  • Patent number: 7308632
    Abstract: A method and apparatus for the utilization of on-chip, programmable resources to implement a signal distortion characterization circuit. Programmable logic resources, such as programmable delay lines and phase shifting circuits, are utilized to sample the logic value of a test signal after the test signal has traversed a path under test (PUT). A counter is used to determine the number of logic high valued samples and the number of logic low valued samples during a test period. A ratio is then taken to determine the resulting duty cycle for the test period.
    Type: Grant
    Filed: August 11, 2005
    Date of Patent: December 11, 2007
    Assignee: Xilinx, Inc.
    Inventors: Himanshu J. Verma, Paul T. Nguyen, Paul A. Swartz
  • Patent number: 7263117
    Abstract: A delay line including analog delay elements each having a selectively adjusted coarse and fine delay portion is described. The coarse delay portion receives an input clock signal and generates a ramp signal having a slope based on a predetermined coarse delay setting. The fine delay portion generates a threshold voltage based on a predetermined fine delay setting. A comparator compares the coarse delay ramp signal voltage with the fine delay threshold voltage and generates an output clock signal when the ramp signal voltage surpasses the fine delay threshold voltage. The coarse delay is linearly adjustable based on a 32-bit binary input signal and the fine delay is binary-weight adjusted based on a 5-bit binary input signal. Both the coarse and fine delay portions are controlled by delay line control circuitry which compares a feedback version of the output clock signal with the input clock signal and provides control signals to increment or decrement coarse and fine delay in the delay line.
    Type: Grant
    Filed: April 9, 2003
    Date of Patent: August 28, 2007
    Assignee: Mosaid Technologies Incorporated
    Inventors: Ki-Jun Lee, Gurpreet Bhullar
  • Patent number: 7071751
    Abstract: A counter-controlled delay line for delaying signals having a wide range of possible frequencies is described. The counter-controlled delay line receives an input clock and produces a delayed output clock based on a delay select control signal. The delay select control signal includes three granularities of delay: a coarse grain, medium grain, and fine grain. The coarse grain delay is provided by a counter. The medium grain delay is provided by a sequential starter circuit coupled to an oscillator. The fine grain delay is provided by a trim unit.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: July 4, 2006
    Assignee: Xilinx, Inc.
    Inventor: Alireza S. Kaviani
  • Patent number: 7068087
    Abstract: A method and apparatus for an improved timer circuit and improved pulse width detection includes initiating a ramp timer and setting a timer latch output level substantially simultaneously in response to the occurrence of an input signal. The occurrence of the input signal also causes a counter to be enabled to count clock cycles. The ramp timer signal of the ramp timer is frozen (i.e., paused) by a timer control circuit, upon the occurrence of a first clock cycle following the enabling of the counter. The counter then counts a predetermined number of clock cycles after the ramp timer signal is frozen and, upon the occurrence of a last one of a predetermined number of clock cycles, generates a terminal count signal. Upon receiving the terminal count signal, the timer control circuit unfreezes ramp timer signal. The ramp timer runs until completion at which time the ramp timer generates an end of ramp control signal. The control signal is communicated to timer latch to reset timer latch output level.
    Type: Grant
    Filed: February 24, 2004
    Date of Patent: June 27, 2006
    Assignee: Tektronix, Inc.
    Inventors: John F. Stoops, Steven K. Sullivan
  • Patent number: 7015740
    Abstract: A circuit including a sensing circuit, which includes a first delay circuit and a tuning circuit. The tuning circuit includes a sense counter and a reference counter. The sense counter is coupled to the first delay circuit and is configured to count a number of oscillations provided by the first delay circuit and provide a notification to the tuning circuit when the sense counter reaches a threshold value. The reference counter is coupled to the sense counter and a reference clock. The reference counter is configured to store a reference time which represents a time elapsed for the sense counter to reach the threshold value. Also included in the circuit is a second delay circuit coupled to the sensing circuit.
    Type: Grant
    Filed: October 28, 2002
    Date of Patent: March 21, 2006
    Assignee: Cisco Technology, Inc.
    Inventors: Eugene M. Feinberg, Richard F. Paul, Philip R. Manela
  • Patent number: 6819157
    Abstract: A delay compensation circuit that determines the effects of process, voltage, and temperature (PVT) conditions of a chip by measuring the effective delay time of delay components inside the chip. The delay compensation circuit includes a plurality of sampler modules, each of which receives a delayed clock signal from one of a series of delay cells within a tapped delay circuit. The delay compensation circuit generates an output value based on the total number of sampling modules that lock into a fixed input signal using the delayed clock signals. Since the delay time of each delay cell changes based on variations of PVT conditions, the output values generated by the delay compensation circuit are determinate of PVT conditions in the chip. These output values can be used to design components to compensate for variances in PVT conditions or to control a variable delay component based on detected PVT conditions.
    Type: Grant
    Filed: November 15, 2001
    Date of Patent: November 16, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Xianguo Cao, Obed Duardo, Bo Ye
  • Patent number: 6715086
    Abstract: A time-enhanced input device driver for a data processing system is capable of generating time-enhanced output in response to input signals. The input device driver receives a first input-event signal followed by a second input-event signal. In response to the second input-event signal, the input device driver generates a character code and an associated time-span code. The time-span code reflects the amount of time that separated the first input-event signal from the second. In an illustrative embodiment, the first and second input-event signals may comprise a key-down signal from a particular key on a keyboard and a key-up signal from that key respectively, in which case the generated character code would correspond to that key.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: March 30, 2004
    Assignee: International Business Machines Corporation
    Inventors: Maria Azua Himmel, Herman Rodriguez
  • Patent number: 6574169
    Abstract: A delay test system includes an electronic circuit, such as a normal circuit which has a portion to be tested and a plurality of flip-flop circuits. In this event, each of flip-flop circuits is serially connected to each other to perform a delay test for said normal circuit. Further, a first clock input terminal is connected to the flip-flips and a normal circuit to input a normal mode clock signal. Moreover, a second clock input terminal is connected to the flip-flop circuits and the normal circuit to input a test clock signal. With such a structure, an input and output operation of data signals is carried out in synchronism with edge timings determined by both the normal mode clock signal in the normal mode on the condition that the test clock signal is not supplied to the second clock input terminal. On the other hand, the first and second clock input terminals are separately driven by the normal mode clock signal and the test clock signal in the test mode.
    Type: Grant
    Filed: August 3, 2000
    Date of Patent: June 3, 2003
    Assignee: NEC Electronics Corporation
    Inventor: Hisashi Yamauchi
  • Patent number: 6570426
    Abstract: In a delay circuit, a voltage detecting circuit is additionally provided. This voltage detecting circuit detects such a condition that a voltage appeared at a measuring terminal of the delay circuit is shifted from a predetermined voltage range for a time duration longer than, or equal to a preset time duration. Even when the measuring terminal of the delay circuit is short-circuited to the power supply voltage, or the ground potential, this delay circuit firmly inverts the output signal level based on delay time set by an internal delay circuit.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: May 27, 2003
    Assignee: Seiko Instruments Inc.
    Inventor: Takao Nakashimo
  • Patent number: 6466520
    Abstract: A circuit measures the signal propagation delay through a selected test circuit. The test circuit is provided with a feedback path so that the test circuit and feedback path together form a free-running oscillator. The oscillator then automatically provides its own test signal that includes alternating rising and falling signal transitions on the test-circuit input node. A phase discriminator samples the output of the oscillator and accumulates data representing the signal propagation delay of either rising or falling signal transitions propagating through the test circuit. The worst-case delay associated with the test circuit can then be expressed as the longer of the two. Knowing the precise worst-case delay allows IC designers to minimize the guard band and consequently guarantee higher speed performance.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: October 15, 2002
    Assignee: Xilinx, Inc.
    Inventors: Gil A. Speyer, David L. Ferguson, Daniel Y. Chung, Robert D. Patrie, Robert W. Wells, Robert O. Conn
  • Patent number: 6313679
    Abstract: A timing circuit which is used to synchronize different circuit to each other. The timing circuit includes adjustable delay apparatus which delay an input signal with a predetermined value. The timing circuit uses counting devices to count the input signal and the delayed output signal and thereby provides a simple and more cost effective timing circuit.
    Type: Grant
    Filed: April 20, 1999
    Date of Patent: November 6, 2001
    Assignee: U.S. Philips Corporation
    Inventors: Cornelis G. M. Van Asma, Matheus J. G. Lammers
  • Patent number: 6232845
    Abstract: A circuit measures a signal propagation delay through a series of memory elements. In one embodiment the memory elements are configured in series so that together they form a delay circuit. In another embodiment the memory elements are configured in a loop to form a ring oscillator. Each memory element propagates a signal to a subsequent memory element so that the time the signal takes to traverse all of the memory elements is proportional to the average delay induced by the individual elements. This proportionality provides an effective means for measuring the delays of those components. Various embodiments of the invention measure the speeds at which memory elements can be preset, cleared, written to, read from, or clock enabled.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: May 15, 2001
    Assignee: Xilinx, Inc.
    Inventors: Christopher H. Kingsley, Trevor J. Bauer, Robert W. Wells, Robert D. Patrie
  • Patent number: 6215345
    Abstract: The semiconductor device for setting a delay time, according to the present invention, comprises: a plurality of serially connected delay circuits into which a reference signal is input; a selector switch for selecting one of delay signals output from connection points between the delay circuits; and an internal selection signal generator for producing a selection signal for switching the selector switch to select one of the connection points.
    Type: Grant
    Filed: March 19, 1999
    Date of Patent: April 10, 2001
    Assignee: NEC Corporation
    Inventors: Yasuo Yashiba, Toshichika Sakai, Takaharu Fujii
  • Patent number: 6172546
    Abstract: A time delay from a triggering event to switching of an output signal in a microelectronic device can be adjusted to compensate for various characteristics of the electronic device. The characteristics include temperature, voltage, and manufacturing process conditions. The time delay is adjusted using a variable delay circuit having multiple delay cells that are selectively coupled to control the time delay. The conditions of the electronic device are detected using a process sensor, which includes an oscillator having a frequency that is sensitive to variations in the conditions.
    Type: Grant
    Filed: October 8, 1999
    Date of Patent: January 9, 2001
    Assignee: Intel Corporation
    Inventors: Jonathan H. Liu, Michael J. Allen, James W. Conary, David P. DiMarco, Jeffrey L. Miller
  • Patent number: 6144262
    Abstract: A circuit measures a signal propagation delay through a series of memory elements on a programmable logic device. In one embodiment, a number of latches are configured in series. Each latch is initialized to store a logic zero. The first latch is then clock-enabled so that the output of the latch rises to a logic one. The logic one from the first latch clock-enables the second latch in the series so that the output of the second latch rises to a logic one, which in turn enables the next latch in the series. The time required for a rising edge to traverse the entire sequence of latches is the cumulative time required for the output of each latch to change in response to a clock-enable signal. Consequently, the delay through the series of latches provides a measure of the time required for one of the latches to respond to a clock-enable signal.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: November 7, 2000
    Assignee: Xilinx, Inc.
    Inventor: Christopher H. Kingsley
  • Patent number: 6134191
    Abstract: A circuit separately measures one or both of the rising-edge and falling-edge signal propagation delays through a signal path of interest. The greater of these delays can then be used to establish a worst-case delay for the signal path. The worst-case delay can be used, in turn, to create accurate timing specifications for logic circuits that include similar or identical signal paths. To determine the delay through the signal path, the signal path is used with a second, typically identical, signal path to create alternating feedback paths of an oscillator. The oscillator is configured to output a test-clock signal having a period proportional to either the rising- or falling-edge delays through the two signal paths. The test-signal transitions are counted over a predetermined time period to establish the average period of the oscillator. Finally, the average period of the oscillator is related to the average signal propagation delay through the signal path of interest.
    Type: Grant
    Filed: February 26, 1999
    Date of Patent: October 17, 2000
    Assignee: Xilinx, Inc.
    Inventor: Peter H. Alfke
  • Patent number: 6130566
    Abstract: The invention relates to a wave form shaping circuit, which outputs signals after shaping the input signal to a duty 50% wave form regardless of whether or not input signals are of duty 50%, wherein a duty determination circuit is provided, which determines and instructs the timing position of duty 50% of clock signals to be outputted, upon receiving a timing signal prepared by a timing generation circuit 2.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: October 10, 2000
    Inventor: Akira Yokomizo
  • Patent number: 6127870
    Abstract: An output delay circuit has a counter which is reset at every input of an input signal of a first signal state thereto and counts input clocks while the input signal of a second signal state is inputted thereto; a comparator for comparing an accumulated number of the input clocks having been counted by the counter with a predetermined clock number set in advance; and a logic circuit for, when it is determined by the comparator that the accumulated number of the input clocks is less than the predetermined clock number, outputting an output signal having a signal state same as the first signal state of the input signal, while for, when it is determined by the comparator that the accumulated number of the input clocks is not less than the predetermined clock number, outputting an output signal having a signal state same as the second signal state of the input signal
    Type: Grant
    Filed: July 23, 1998
    Date of Patent: October 3, 2000
    Assignee: Matsushita Electric Works, Ltd.
    Inventor: Atsuo Fukuda
  • Patent number: 6097224
    Abstract: The invention relates to a wave form shaping circuit, etc. which outputs signals after shaping the input signal to a duty 50% wave form regardless of whether or not input signals are of duty 50%, wherein a duty determination circuit is provided, which determines and instructs the timing position of duty 50% of clock signals to be outputted, upon receiving a timing signal prepared by a timing generation circuit 2.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: August 1, 2000
    Inventor: Akira Yokomizo
  • Patent number: 6091794
    Abstract: A synchronous counter circuit having a plurality of bit counting stages, each corresponding to a bit position for representing counts, from a least significant bit to a most significant bit. Each bit counting stage includes a flip-flip circuit and a synchronization circuit and each includes circuitry for receiving a pulse train clock signal, synchronously counting said clock signal and outputting an output bit signal corresponding to said counters' stage bit position. The bit counting stages are arranged in two groups, a reset group and a counting group, such that the output bit signal of said flip-flop circuit of the reset group synchronizes data propagation between each bit counting stage of the counting group.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: July 18, 2000
    Assignee: STMicroelectronics, Inc.
    Inventor: William C. Rogers