Delay Interval Set By Rising Or Falling Edge Patents (Class 327/263)
-
Patent number: 6715086Abstract: 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: GrantFiled: June 30, 1999Date of Patent: March 30, 2004Assignee: International Business Machines CorporationInventors: Maria Azua Himmel, Herman Rodriguez
-
Publication number: 20030231041Abstract: 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: ApplicationFiled: April 9, 2003Publication date: December 18, 2003Inventors: Ki-Jun Lee, Gurpreet Bhullar
-
Patent number: 6657473Abstract: A delay circuit includes a delay part delaying a signal by a delay time which can be varied based on a control current, and a control current adjustment circuit adjusting the control current so that the delay time changes linearly based on a variation in a resistance value.Type: GrantFiled: September 5, 2000Date of Patent: December 2, 2003Assignee: Fujitsu LimitedInventor: Satoshi Eto
-
Patent number: 6653877Abstract: A plurality of internal circuits each include a respective clock adjusting circuit that adjusts the phase of a clock signal given by a clock buffer. Even if a difference in delayed amount of the clock signal is generated by drawing clock interconnections, a different adjustment can be made for each internal circuit, whereby the operation of synchronized circuits respectively included in the plurality of internal circuits can be improved.Type: GrantFiled: December 22, 2000Date of Patent: November 25, 2003Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Mitsunori Tsujino
-
Patent number: 6646488Abstract: Methods and systems for controlling delay relatively independent of process, supply-voltage, and/or temperature (“PVT”) variations include sensing an output signal after a number of inverters and activating different numbers of transistors and/or adjusting strength of transistors in a delay path to compensate for PVT variations. In an embodiment, a waveform is received, delayed, and output to an output terminal using at least one relatively low-power device. Supplemental output power is provided by at least one relatively high-power device until the output waveform exceeds a threshold.Type: GrantFiled: June 27, 2002Date of Patent: November 11, 2003Assignee: Broadcom CorporationInventor: Janardhanan S. Ajit
-
Patent number: 6617903Abstract: An inverter circuit includes a first transistor connected between an input terminal and a gate of a second transistor, a second transistor connected between power supply voltage and an output terminal, a third transistor connected between an input terminal and a gate of a fourth transistor and a fourth transistor connected between a ground and the output terminal.Type: GrantFiled: July 10, 2001Date of Patent: September 9, 2003Assignee: Oki Electric Industry Co., Ltd.Inventor: Yukio Kawamura
-
Patent number: 6614278Abstract: A delay circuit has an input node receives an input pulsed signal. A buffer transfers the input signal to a floating node. A detector outputs to an output node an output voltage that has a first level, if the voltage at the floating node is below a threshold, and a second level otherwise. Two similar branches are used, one for controlling delays in the rising transitions and one for controlling delays in the falling transitions. For each branch, a reference terminal carries a reference voltage for biasing the floating node. A capacitor and a switch are coupled between the reference terminal and the floating node. The switch opens and closes responsive to the output voltage. When it opens, it shorts out the capacitor. An optional phase detector and delay code generator may be in a feedback arrangement, for continuously adjusting the reference voltages.Type: GrantFiled: May 29, 2001Date of Patent: September 2, 2003Assignee: Samsung Electronics Co., Ltd.Inventors: Kyo-hyoun Kim, Dae-Hyun Chung
-
Publication number: 20030128063Abstract: The present invention is directed to a transition delay circuit. The transition delay circuit includes a delay circuit which is responsive to an input signal. The transition delay circuit produces an output signal at a common node. The transition delay circuit also includes a first MOS capacitor connected between the input signal and the common node and a second MOS capacitor connected between the input signal and the common node. A method for delaying an input signal to a buffer circuit is also disclosed.Type: ApplicationFiled: December 11, 2002Publication date: July 10, 2003Inventor: Eric J. Stave
-
Patent number: 6525583Abstract: A compensation circuit includes at least one of an n-channel device connected to oppose a high-to-low transition and a p-channel device connected to oppose a low-to high transition. The n-channel and p-channel devices may be diodes, transistors, or transistors connected to function as diodes. The n-channel and p-channel devices may be connected to a large variety of devices and circuits, such as phase locked loops, delay locked loops, clock circuits, or any circuit which requires two balanced paths, one through n-channel devices and one through p-channel devices, to compensate for process variations. Methods for balancing a circuit path and compensating for process variations are also disclosed.Type: GrantFiled: January 16, 2002Date of Patent: February 25, 2003Assignee: Micron Technology, Inc.Inventor: Brian W. Huber
-
Patent number: 6515529Abstract: The present invention is directed to a transition delay circuit. The transition delay circuit includes a delay circuit which is responsive to an input signal. The transition delay circuit produces an output signal at a common node. The transition delay circuit also includes a first MOS capacitor connected between the input signal and the common node and a second MOS capacitor connected between the input signal and the common node. A method for delaying an input signal to a buffer circuit is also disclosed.Type: GrantFiled: August 13, 2001Date of Patent: February 4, 2003Assignee: Micron Technology, Inc.Inventor: Eric J. Stave
-
Publication number: 20020180505Abstract: A delay circuit has an input node receives an input pulsed signal. A buffer transfers the input signal to a floating node. A detector outputs to an output node an output voltage that has a first level, if the voltage at the floating node is below a threshold, and a second level otherwise. Two similar branches are used, one for controlling delays in the rising transitions and one for controlling delays in the falling transitions. For each branch, a reference terminal carries a reference voltage for biasing the floating node. A capacitor and a switch are coupled between the reference terminal and the floating node. The switch opens and closes responsive to the output voltage. When it opens, it shorts out the capacitor. An optional phase detector and delay code generator may be in a feedback arrangement, for continuously adjusting the reference voltages.Type: ApplicationFiled: May 29, 2001Publication date: December 5, 2002Applicant: Samsung Electronics Co., LtdInventors: Kyu Hyoun Kim, Dae-Hyun Chung
-
Patent number: 6469557Abstract: An object of the present invention is to simply and rapidly adjust a delay time of a delayed clock signal in accordance with a change in frequency of an input clock signal. The present invention comprises: a pulse generating circuit for generating a pulse signal PULSE with a trailing edge of an input clock signal as a reference; an inverter chain consisting of a plurality of inverters; a pair of inverter chains for sequentially delaying output signals from the pulse generating circuit; a plurality of NOR gates for adjusting a delay time of each inverter in the inverter chain; and a plurality of NAND gates for similarly adjusting a delay time of each inverter in the inverter chain. Since the delay time of the delayed clock signal in a next cycle is set based on the pulse signal generated based on a trailing edge of the input clock signal, even if a cycle of the input clock signal varies, the delay time of the delayed clock signal can be rapidly changed in accordance with this variation.Type: GrantFiled: May 29, 2001Date of Patent: October 22, 2002Assignee: Kabushiki Kaisha ToshibaInventor: Osamu Hirabayashi
-
Patent number: 6462597Abstract: Circuit techniques provide different trip points for a rising-edge and for a falling-edge input to a logic gate. Adjustment of the gate trip point for a rising-edge input may be independently adjusted to that for the falling-edge input, and vice versa. Different circuit topologies are provided for delay chains on integrated circuits. Each implementation allows flexibility in delay elements through metal options to allow modifying delay chain delays with simple metal-only layout changes. Delay chains are used in integrated circuits to produce either a constant delay or to track another circuit delay.Type: GrantFiled: January 31, 2000Date of Patent: October 8, 2002Assignee: Altera CorporationInventor: Andy L. Lee
-
Publication number: 20020135413Abstract: A delay circuit includes a first inverter connected to a supply voltage, and has an input for receiving an input signal. A delay regulating transistor is connected between the first inverter and a first voltage reference, and has a control terminal for receiving a biasing voltage. A capacitor is connected between an output of the first inverter and the first voltage reference. A second inverter is connected to the output of the first inverter for outputting a delayed output signal. An auxiliary current path is in parallel to the delay regulating transistor for allowing a portion of a discharge current from the capacitor to flow therethrough. The portion of the discharge current is proportional to the supply voltage. The auxiliary current path includes a diode connected to the first inverter, and a second transistor connected between the diode and the first voltage reference. The second transistor has a control terminal for receiving the biasing voltage.Type: ApplicationFiled: January 31, 2001Publication date: September 26, 2002Applicant: STMincroelectronics S.r.I.Inventors: Francesco Tomaiuolo, Fabrizio Campanale, Salvatore Nicosia, Luca Giuseppe De Ambroggi, Promod Kumar
-
Patent number: 6434061Abstract: A compensation circuit includes at least one of an n-channel device connected to oppose a high-to-low transition and a p-channel device connected to oppose a low-to high transition. The n-channel and p-channel devices may be diodes, transistors, or transistors connected to function as diodes. The n-channel and p-channel devices may be connected to a large variety of devices and circuits, such as phase locked loops, delay locked loops, clock circuits, or any circuit which requires two balanced paths, one through n-channel devices and one through p-channel devices, to compensate for process variations. Methods for balancing a circuit path and compensating for process variations are also disclosed.Type: GrantFiled: August 31, 2000Date of Patent: August 13, 2002Assignee: Micron Technology, Inc.Inventor: Brian W. Huber
-
Patent number: 6426661Abstract: A voltage-compensated, constant delay clock buffer for a chip clock distribution circuit employs a variable gain circuit to dynamically control the delay through the first inverter stage. In the presence of no voltage rail collapse the first stage gain is set high which results in a nominal delay through the first stage. As voltage rail collapse occurs local to the clock buffer circuit, the gain on the first stage is reduced to yield a smaller than nominal delay through the first stage in such a way as to compensate for the increased delay in the subsequent stage or stages. The control circuit is responsive to a first voltage rail and a second voltage rail to provide dynamic control of the delay through the first inverter stage. The circuit can compensate the circuit to handle a plurality of second inverter stages with the control circuit adjusting the delay of said first inverter stage, and with the control circuit remaining responsive to a first voltage rail and a second voltage rail.Type: GrantFiled: August 20, 2001Date of Patent: July 30, 2002Assignee: International Business Machines CorporationInventor: Brian W. Curran
-
Patent number: 6407602Abstract: A method for eliminating races commences with the testing of an integrated circuit for races. If a clock signal which is produced by the integrated circuit is deemed to be a cause of races, at least one transistor region is clipped from an output driver of a clock gater which produces the clock signal. The clipping is performed by reconstructing at least one mask which is used to define the output driver during fabrication of the integrated circuit. In a similar fashion, a method for increasing the rise/fall time of clock edges in an integrated circuit commences with the identification of a clock signal with a clock edge having a poor rise/fall time. The rise/fall time of such a clock edge is increased by clipping at least one transistor region from an output driver of a clock gater which produces the clock signal. Once again, the clipping is performed by reconstructing at least one mask which is used to define the output driver during fabrication of the integrated circuit.Type: GrantFiled: November 2, 2001Date of Patent: June 18, 2002Assignee: Hewlett-Packard CompanyInventor: Rajakrishnan Radjassamy
-
Patent number: 6392461Abstract: A clock modulator for in-vehicle electronic equipment requiring an EMI countermeasure optimally reduces undesired radiant noise by a low spectral dispersion number. A delay circuit has delay buffers DB0 to DB30 connected in series with each other, each outputting an output pulse delayed from an input pulse by a phase delay time &tgr;, and a selection circuit sequentially selecting an output pulse outputted from each of the delay buffers DB0 to DB30. Adjustment is made such that with respect to an input CLK inputted to the delay buffer DB0, a phase variation amount of the output pulse from the delay buffer DB0 and a phase variation amount of the output pulse from the delay buffer DB30 are near ±45° when a phase of the output pulse from the delay buffer DB15, at a center position of the delay buffers DB0 to DB30, is made a reference.Type: GrantFiled: February 1, 2001Date of Patent: May 21, 2002Assignee: Fujitsu LimitedInventors: Hideo Nunokawa, Naoto Emi, Tomonari Morishita
-
Patent number: 6388480Abstract: A delay locked loop having improved synchronization times has a variably adjustable delay line which accepts two incoming clock pulses. As each pulse propagates through the delay line an edge of the pulse toggles or retoggles a shift bit corresponding to a delay element. When the first pulse reaches the end of the delay line, the status of the shift bits is frozen, and a starting point for a synchronization sequence begins at the transition point between toggled and retoggled shift bits.Type: GrantFiled: August 28, 2000Date of Patent: May 14, 2002Assignee: Micron Technology, Inc.Inventors: Eric T. Stubbs, James E. Miller
-
Patent number: 6342797Abstract: A delayed locked loop (DLL) clock generator in DDR SDRAM is disclosed. The DLL clock generator comprises a pulse generator for generating a pulse signal of which a pulse width corresponds to a predetermined delay time; a first delay chain including a plurality of delay means, for delaying the pulse signal by a predetermined delay time in order; and a second delay chain having the same delay time as the first delay chain, for delaying an external clock signal responsive to an output signal from the delay means. The second clock signal is generated through the same path as a path through which the external clock signal is inputted and the delayed external clock signal is outputted.Type: GrantFiled: December 30, 1999Date of Patent: January 29, 2002Assignee: Hyundai Electronics Industries Co., Ltd.Inventor: Seong-Hoon Lee
-
Patent number: 6342799Abstract: The invention relates in general to error correcting programmable pulse generator, and more particularly to a programmable pulse generator that removes errors due to manufacturing tolerances, power supply variation, and temperature. A method of modifying a signal from a source includes generating a signal and varying a first and second impedance to control the rise and fall time and average level of the signal to produce an output signal, wherein a plurality of voltage levels are modified. Then, varying a first reference current to produce a second reference current that provides a source for a plurality of currents, wherein the plurality of currents includes a first current, a second current and a third current. In addition, scaling the second reference current producing the first current, second current and third current to correct the plurality of modified voltage levels, wherein errors induced by an external environment and manufacturing tolerances are reduced.Type: GrantFiled: October 6, 2000Date of Patent: January 29, 2002Assignee: Level One Communications, Inc.Inventor: Chris Nilson
-
Patent number: 6313681Abstract: A variable delay circuit has a positive logic variable delay circuit which delays an edge of a signal which is input through an input terminal and a negative logic variable delay circuit which delays an edge of the signal input through an input terminal. Only an edge delayed in accordance with the set time is extracted from all the edges of a signal supplied from the positive logic variable delay circuit and all the edges of a signal supplied from the negative logic variable delay circuit in an extracting circuit of the variable delay circuit.Type: GrantFiled: October 27, 1999Date of Patent: November 6, 2001Assignee: NEC CorporationInventor: Kiyoshi Yoshikawa
-
Patent number: 6278310Abstract: The present invention is directed to a transition delay circuit. The transition delay circuit includes a delay circuit which is responsive to an input signal. The transition delay circuit produces an output signal at a common node. The transition delay circuit also includes a first MOS capacitor connected between the input signal and the common node and a second MOS capacitor connected between the input signal and the common node. A method for delaying an input signal to a buffer circuit is also disclosed.Type: GrantFiled: April 25, 2000Date of Patent: August 21, 2001Assignee: Micron Technology, Inc.Inventor: Eric J. Stave
-
Patent number: 6278334Abstract: A voltage controlled oscillator is provided in the form of two ring oscillators 30 and 32. Each oscillator stage 14 includes an invertor 16, a level change accelerating circuit 18 and a level change decelerating circuit 20. The level change accelerating circuit 18 is responsive to an input control signal Vctrl to increase the oscillator frequency by decreasing the propagation delay through the invertor 16. The level change decelerating circuit 20 is responsive to the input control signal Vctrl to decrease the oscillator frequency by increasing the propagation delay through the invertor 16. Pairs of opposing invertors 34, 36, 38, 40 and 42 disposed between output signal lines of corresponding oscillator stages 14 in the two ring oscillators 30 and 32 serve to lock the two ring oscillators in antiphase.Type: GrantFiled: November 29, 1999Date of Patent: August 21, 2001Assignee: Arm LimitedInventor: Eric Bernard Schorn
-
Patent number: 6259283Abstract: A clock doubler circuit and method that accept an input clock signal and provide therefrom an output clock signal having twice the frequency of the input clock signal. One circuit according to the invention includes an input clock terminal supplying a input clock signal, and a delay line driven by the input clock signal and supplying a plurality of intermediate clock signals delayed from the input clock signal by incremental unit delays. A clock multiplexer selects from among these intermediate clock signals, under control of a multiplexer control circuit, the clock signal that is most nearly 90 degrees offset from the input clock signal. The selected clock signal is then combined with the input clock signal in an output clock generator to generate an output clock signal having twice the frequency of the input clock signal. In one embodiment, the clock doubler circuit includes a delay stage comprising a delay element that can selectively add a half-unit delay to the input clock signal.Type: GrantFiled: January 28, 2000Date of Patent: July 10, 2001Assignee: Xilinx, Inc.Inventor: Andy T. Nguyen
-
Patent number: 6255878Abstract: A precision delay circuit having two delay chains to provide equal delay periods is described. A rising edge of an input pulse signal is supplied to the first delay chain and the falling edge is supplied to the second delay chain. The resultant output signal maintains the pulse width of the input signal and pulse distortion is minimized. In another aspect, a delay circuit for generating a delayed assertion signal that does not maintain the width of the original input signal pulse and which is substantially immune to noise problems is described. An assertion edge of a resultant pulse is timed by the incoming pulse, but the de-assertion edge is timed by the delayed de-assertion edge of the incoming pulse.Type: GrantFiled: May 7, 1999Date of Patent: July 3, 2001Assignee: LSI Logic CorporationInventors: Coralyn S. Gauvin, William K. Petty, Brian K. Herbert
-
Patent number: 6233205Abstract: 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. These signal transitions are counted over a predetermined time period to establish the period of the oscillator. The period of the oscillator is then related to the average signal propagation delay through the test circuit. The invention can be applied to synchronous components that might fail to oscillate by connecting the asynchronous set or clear terminal to the output terminal so that the oscillator oscillates at a frequency determined by the clock-to-out delay of those components.Type: GrantFiled: July 14, 1998Date of Patent: May 15, 2001Assignee: Xilinx, Inc.Inventors: Robert W. Wells, Robert D. Patrie, Robert O. Conn
-
Patent number: 6226230Abstract: A timing signal generating apparatus capable of automatically detecting any erroneous set state that a pulse duration of a test pattern signal and a time duration between adjacent two pulses of the test pattern signal have been set in a program with the durations being shorter than corresponding limit values respectively, and a method of detecting any set error to the program for a timing signal. At the outside of a clock generator 113A for generating a set pulse PS and a reset pulse PR are provided a fourth latch circuit 16 for latching therein an integer delay signal MT outputted from a down-counter 11 of an integer delay giving device 10, and a fifth latch circuit 17 for latching therein an odd value MDAT outputted from a first latch circuit 12 of the integer delay giving device 10, thereby to detect a time duration from the set pulse until the reset pulse or a time duration from the reset pulse until the set pulse.Type: GrantFiled: June 28, 1999Date of Patent: May 1, 2001Assignee: Advantest CorporationInventor: Naoyoshi Watanabe
-
Patent number: 6222403Abstract: A slew rate output circuit includes a switching device connected to an output terminal, a driver circuit connected to the switching device for driving the switching device, and a control circuit connected to the driver circuit for controlling the driver circuit in accordance with an input signal so that, in an initial time period after a change in level of the input signal, the average slew rate is higher than that in a subsequent time period.Type: GrantFiled: June 2, 1999Date of Patent: April 24, 2001Assignee: NEC CorporationInventor: Tsuyoshi Mitsuda
-
Patent number: 6222393Abstract: A circuit for generating a pulse signal in response to an input signal. The circuit provides a pulse width for the pulse signal. A first logic device receives the input signal and generates a first intermediate signal. A delay device is coupled to the first logic device and receives the first intermediate signal. The delay device generates a second intermediate signal in response to the first intermediate signal after a period of time. The second intermediate signal has the same state as the second intermediate signal. A second logic device is coupled to both the first logic device and the delay device. The second logic device generates the pulse signal in response to the first intermediate signal.Type: GrantFiled: July 20, 1999Date of Patent: April 24, 2001Assignee: Cypress Semiconductor CorporationInventors: Shailesh Shah, Gregory J. Landry
-
Patent number: 6208184Abstract: A method and circuit are provided for delaying a transition in a digital data stream fed to a write head of a mass storage device by a certain time interval when the transition occurs at a clock phase following the one during which a preceding transition has occurred, for pre-compensating intersymbol nonlinear interference effects suffered when reading the stored data. The method includes feeding digital data stream to be stored and a clock signal to a first circuit and outputting a pair of digital streams from the first circuit. The first stream assumes a first logic value every time a transition of the input stream occurs during a clock phase not successive to a clock phase during which a transition of the input stream has occurred. The second stream assumes the first logic value every time a transition of the input stream occurs during a clock phase following a clock phase during which a transition has taken place in the input stream.Type: GrantFiled: November 30, 1999Date of Patent: March 27, 2001Assignee: STMicroelectronics S.r.l.Inventors: Marco Demicheli, Melchiorre Bruccoleri, Maurizio Malfa, Giacomino Bollati
-
Patent number: 6198326Abstract: A delay time compensation circuit for a clock buffer includes first and second toggle flip-flops multiplying an input clock signal and a delay clock signal which is delayed by an input buffer, respectively, a time interval extraction chain extracting a time interval between a rising edge of the input clock signal and a rising edge of the delay clock signal in accordance with clock signals multiplied in the first and second toggle flip-flops, and a variable delay chain delaying the input clock signal by a time interval extracted from the time interval extraction chain. The circuit employs a ½ multiplied clock signal and operates without regard to a duty cycle of an input clock signal, thereby compensating for all the delay time within the cycle of the input clock signal.Type: GrantFiled: November 13, 1998Date of Patent: March 6, 2001Assignee: Hyundai Electronics Industries Co., Ltd.Inventors: Joong-Ho Choi, Boo Yong Park, Jin-Hong Ahn
-
Patent number: 6175605Abstract: An edge triggered adjustable delay line circuit to determine the difference in time between a transition of a first signal and a transition of the second signal; a variably additive delay line circuit that will delay an input signal by a delay factor that is the sum of a multiplicity of variable delay factors; and a timing synchronization circuit to synchronize an internal timing signal with an external timing signal within one timing cycle is described. The timing synchronization circuit will utilize the edge triggered delay line and the variably additive delay line circuits to determine the synchronization parameters to synchronize the internal timing signal with the external timing signal.Type: GrantFiled: March 25, 1998Date of Patent: January 16, 2001Assignee: Vanguard International Semiconductor CorporationInventor: Min-Hwa Chi
-
Patent number: 6172544Abstract: A timing signal generation circuit to be used in a semiconductor test system which is not affected by voltage changes or temperature changes.Type: GrantFiled: February 25, 1999Date of Patent: January 9, 2001Assignee: Advantest Corp.Inventor: Shigeru Sugamori
-
Patent number: 6157234Abstract: An integrated circuit has a first circuit which receives an input signal and outputs a first output signal, wherein the first output signal is produced by changing the pulse width of the input signal, a second circuit which receives the first output signal and outputs a second output signal, wherein the second output signal is produced by delaying the first output signal and a control circuit. The control circuit has a first control circuit which receives the first and second output signals and controls the first circuit based on the first and second output signals and a second control circuit which receives the first and second output signals and controls the second based on the first and second output signals.Type: GrantFiled: January 19, 1999Date of Patent: December 5, 2000Assignee: NEC CorporationInventor: Hiroshi Yamaguchi
-
Patent number: 6154075Abstract: The invention relates in general to error correcting programmable pulse generator, and more particularly to a programmable pulse generator that removes errors due to manufacturing tolerances, power supply variation, and temperature. A method of modifying a signal from a source includes generating a signal and varying a first and second impedance to control the rise and fall time and average level of the signal to produce an output signal, wherein a plurality of voltage levels are modified. Then, varying a first reference current to produce a second reference current that provides a source for a plurality of currents, wherein the plurality of currents includes a first current, a second current and a third current. In addition, scaling the second reference current producing the first current, second current and third current to correct the plurality of modified voltage levels, wherein errors induced by an external environment and manufacturing tolerances are reduced.Type: GrantFiled: May 18, 1999Date of Patent: November 28, 2000Assignee: Level One Communications, Inc.Inventor: Chris Nilson
-
Patent number: 6154072Abstract: A signal production circuit for producing a control signal used in a driving and controlling circuit of a display device externally input to the driving and controlling circuit, using an external interface signal. There is a vertical synchronization signal having a predetermined frequency and a reference clock signal in synchronization with the vertical synchronization signal. The signal production circuit includes: a first counter circuit for counting a number of reference clock signal pulses up to a value of a parameter which is preset based on a time interval of one cycle of the vertical synchronization signal and a predetermined target period.Type: GrantFiled: October 26, 1998Date of Patent: November 28, 2000Assignee: Sharp Kabushiki KaishaInventor: Nobushige Shimada
-
Patent number: 6154078Abstract: The present invention is directed to a transition delay circuit. The transition delay circuit includes a delay circuit which is responsive to an input signal. The transition delay circuit produces an output signal at a common node. The transition delay circuit also includes a first MOS capacitor connected between the input signal and the common node and a second MOS capacitor connected between the input signal and the common node. A method for delaying an input signal to a buffer circuit is also disclosed.Type: GrantFiled: January 7, 1998Date of Patent: November 28, 2000Assignee: Micron Technology, Inc.Inventor: Eric J. Stave
-
Patent number: 6147531Abstract: A write channel in read/write disc drive system for writing data signals to a drive includes a variable delay circuit having a number of selectable taps for correcting for non-linear transition shift; and a delay locked loop circuit responsive to the data signal for controlling the delay of the variable circuit.Type: GrantFiled: July 9, 1998Date of Patent: November 14, 2000Assignee: Analog Devices, Inc.Inventors: Kevin J. McCall, Janos Kovacs
-
Patent number: 6130566Abstract: 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: GrantFiled: October 27, 1997Date of Patent: October 10, 2000Inventor: Akira Yokomizo
-
Patent number: 6114917Abstract: The present invention provides an analog PLL circuit able to shorten a lockin time during which oscillating frequency and phase of a voltage controlling oscillator settle.An analog PLL circuit according to the present invention comprises a divider, a phase comparator, a charge pump, a low pass filter, a voltage controlling oscillator, and a divider. The voltage controlling oscillator has a ring oscillator composed of a plurality of logic inverting elements capable of changing the delay amount. During the reset period, the initial voltage is inputted to the voltage controlling oscillator via the analog switch, and the initial delay amount is set to each of the logic inverting elements. After the reset period finishes, at the point when the rising edge of the standard input signal is firstly inputted, the output of the D flip-flop becomes high level and the ring oscillator begins the oscillating operation.Type: GrantFiled: October 28, 1998Date of Patent: September 5, 2000Assignee: Kabushiki Kaisha ToshibaInventors: Shoj Nakajima, Tamami Hatanaka, Moriyuki Tashiro, Minoru Kiumi, Hirohisa Hirano
-
Patent number: 6111925Abstract: A timing signal synchronization circuit to align an internal timing clock within an integrated circuit with an external system clock with minimum skew and within one cycle of the external system clock is disclosed. A timing signal synchronization circuit has an input buffer subcircuit to receive and delay the external system clock. A fixed delay line circuit is connected to the input buffer subcircuit to delay the received external system clock by a second delay factor to create a first timing signal. The first timing signal is the input to a first and a second measurement delay line. Each will respectively measure a first part and a second part of a period of the first timing signal. A first latch array will receive the measurement and create a first latch signal. A second latch array will receive the measurement and create a second latch signal.Type: GrantFiled: March 25, 1998Date of Patent: August 29, 2000Assignee: Vanguard International Semiconductor CorporationInventor: Min-Hwa Chi
-
Patent number: 6097224Abstract: 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: GrantFiled: April 21, 1999Date of Patent: August 1, 2000Inventor: Akira Yokomizo
-
Patent number: 6081147Abstract: A controlled delay circuit having a first gate chain, and a second gate chain. The first gate chain is used to measure a time difference between a changeover point of a first control signal and a changeover point of a second control signal. The second gate chain, which receives third signals generated in the first gate chain and representing the time difference, is used to provide an appropriate delay time from an input to an output depending on the time difference. The controlled delay circuit is capable of properly controlling the timing of the control signal according to the period of the control signal.Type: GrantFiled: July 30, 1996Date of Patent: June 27, 2000Assignee: Fujitsu LimitedInventor: Yoshinori Okajima
-
Patent number: 6043684Abstract: The integrated circuit includes an input path circuit with an address path having an input buffer for providing address signals to a register. A separate clock path having an input buffer provides a clock signal for clocking the register. The input buffers of both the address path and the clock path include input buffer cells configured to reduce timing delay differences caused by process variations while minimizing current leakage. An exemplary input buffer cell described herein includes a first inverter stage with a pair of NMOS devices connected in series with a PMOS device and a second inverter stage having an additional PMOS device connected along a feedback path around an inverter. The PMOS device along the feedback path operates to assist the pair of NMOS devices to pull a voltage input to the inverter to a high logic state, when an input to the cell is held low, to prevent leakage current through the inverter.Type: GrantFiled: October 29, 1997Date of Patent: March 28, 2000Assignee: Cypress Semiconductor Corp.Inventor: Greg J. Landry
-
Patent number: 6025750Abstract: A digital filter includes a)--a plurality of means for the sampling (10, 11, 12, 13, 20, 21, 22, 30, 31) with different delays, of an incoming signal (S), and b)--means (7) to carry out a linear combination of samples produced by the said sampling means (10, 11, 12, 13, 20, 21, 22, 30, 31). The filter is characterized in that a sampling frequency (F/2) of at least some of the sampling means (20, 21, 22) which are associated with delays longer than some of the other sampling means (10, 11, 12, 13) is lower than a sampling frequency (F) of said other sampling means.Type: GrantFiled: April 28, 1998Date of Patent: February 15, 2000Assignee: AlcatelInventors: Jesus Soto Viso, Jose Luis Del Cerro Hiniesto
-
Patent number: 6023182Abstract: A pulse generating circuit includes a first pulse generating circuit for generating a first output pulse, and a second pulse generating circuit for outputting a second output pulse. Each pulse generating circuit comprises a stack of two n-channel transistors and a reset circuit. The reset circuit includes two p-channel transistors and two inverters and is provided for automatically resetting the pulse generating circuits. The second pulse generating circuit includes a delay element for introducing an additional gate delay in the generation of the second output pulse. The additional gate delay introduces an asymmetry in the output pulses which offsets or cancels a previously introduced asymmetry of an input clock signal to generate an output clock signal having a constant period. Clock gating circuitry is provided for selectively enabling and disabling at least one of said pulse generator circuits.Type: GrantFiled: December 31, 1997Date of Patent: February 8, 2000Assignee: Intel CorporationInventors: Mark S. Milshtein, Thomas D. Fletcher, Terry Chappell
-
Patent number: 6020775Abstract: An adjustable timer circuit capable of producing accurate pulse outputs having a wide range of periods. The timer circuit includes a timing capacitor and an associated current source for producing a reference current having a magnitude which is derived from a reference voltage. A current divider is used to divide the reference current down to a smaller current used for charging the timing capacitor. A comparator circuit is provided for comparing the voltage produced across the timing capacitor with a comparison voltage also derived from the reference voltage. The timing capacitor is discharged in response to the comparator output so that subsequent output pulses can be produced. The current divider is adjustable in response to a mode control signal so that different magnitude charging currents can be produced which results in different magnitude pulse width outputs.Type: GrantFiled: May 9, 1997Date of Patent: February 1, 2000Assignee: Micron Technology, Inc.Inventor: Christophe J. Chevallier
-
Patent number: 5973533Abstract: In a semiconductor gate circuit, an MOS transistor having a low threshold voltage and a standard MOS transistor having threshold voltages of large absolute values are connected in series between an output node and a power supply node. The MOS transistor having the threshold voltage of the large absolute value receives on a gate thereof, a signal preceding in phase a signal applied to a gate of the MOS transistor having the small threshold voltage. In the semiconductor gate circuit, a dependency of input/output characteristics on a power supply voltage is small, and a leak current during standby is reduced. The standard MOS transistor turns on prior to turning on of the low threshold voltage MOS transistor, and turns off when the low threshold voltage MOS transistor turns off. The output node driving current is controlled by the low threshold voltage MOS transistor while a subthreshold leak current is suppressed by the standard transistor.Type: GrantFiled: January 30, 1998Date of Patent: October 26, 1999Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Hideaki Nagaoka
-
Patent number: 5955902Abstract: A voltage controlled delay circuit is comprised of a plurality of stages of delay cells and produces a 2N number of signals delayed behind a reference signal in units of time corresponding to 1/2N the delay time between the reference signal supplied to an input terminal of a first stage delay cell and a signal output from a final stage delay cell. A phase coincidence is achieved between the reference signal and the output signal from the final stage delay cell by a loop including a phase comparator, lowpass filter and voltage controlled delay circuit. An N multiplying logic circuit produces an N multiplied signal from the reference signal with only falls or rises of 2N delay signals.Type: GrantFiled: March 5, 1997Date of Patent: September 21, 1999Assignee: Kabushiki Kaisha ToshibaInventors: Shuichi Takada, Akihiko Yoshizawa