Mosfet Patents (Class 326/97)
  • Patent number: 5821775
    Abstract: The present invention is an improved interface between monotonic and non-monotonic domino logic. A monotonic domino logic block is clocked by CLK. The last stage of the monotonic domino logic is clocked by the delayed clock, DCLK, to extend its evaluation period beyond Phase I by a brief window of time, t.sub.d. The true output and the inverted output of the last stage of the monotonic domino logic block are inputs to a non-monotonic domino evaluation tree. The non-monotonic domino evaluation tree operates while an evaluation control block is ON. The evaluation control block is ON only during that extension of the evaluation period, t.sub.d, for a time less than or equal to the period t.sub.d. Since the output of the last stage of the monotonic logic block remains stable during this extended evaluation period, and the non-monotonic domino evaluation tree operates at most during this window of time, there is no need to use latches or use a dual rail implementation for the monotonic logic.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: October 13, 1998
    Assignee: Intel Corporation
    Inventors: Gaurav G. Mehta, David Harris, S. Deo Singh
  • Patent number: 5811991
    Abstract: A logic circuit comprises an output line, a first switch having an end connected to the output line and another end connected to a power source potential, a second switch having an end connected to the output line and another end connected to a ground potential, and a switching/rectifying circuit, which has an end connected to the output line and another end connected to an intermediate power source potential, for switching/rectifying, in which said intermediate power source potential is higher than the ground potential and lower than the power source potential. With this configuration, said switching/rectifying circuit includes a third switch and a rectifier connected in series.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: September 22, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Daisaburo Takashima
  • Patent number: 5760610
    Abstract: A universal qualified clock buffer circuit for generating high-performance, low-skew local clock signals from a single-phase source clock is presented. The universal qualified clock buffer circuit independently generates a separate clock signal from the single-phase clock signal and provides for conditional signal qualification for those logic circuits which require both control signals and clock signals to regulate the flow of data. An important aspect of the universal qualified clock buffer circuit is that delays on the output signal can be independently controlled. In a CMOS implementation, the delays of both rising and falling edges of the output signal are independently controlled using different FET sizes. To control skew and edge-rate uniformity, the universal qualified clock buffer circuit is capacitively matched to the impedance load of the circuit it drives.
    Type: Grant
    Filed: March 1, 1996
    Date of Patent: June 2, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Samuel D. Naffziger
  • Patent number: 5675264
    Abstract: A differential circuit configuration for generating an inverted signal and a non-inverted signal of an original signal is presented. The waveforms of the output signals are highly synchronous and precise owing to the circuit design which provides matched gate-to-source voltage vs drain-to-source current to produce output trace matching in the output voltage traces of a pair of pull-up transistors with a pair of pull-down transistors. The circuit configuration does not require adjustable capacitors or driving circuits, and is therefore suitable for use in advanced compact devices.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: October 7, 1997
    Assignee: NEC Corporation
    Inventor: Makoto Yoshida
  • Patent number: 5675263
    Abstract: A hot clock adiabatic gate, using CMOS technology, incorporates an ancillary transistor. The gate is energized by multiple clock signals of different phases to reduce power consumption. The output logic voltage of the gate can reach full-rail voltage by allowing the CMOS technology to discharge via the ancillary transistor. The hot clock adiabatic gate and associated ancillary transistor may be incorporated into various logic circuits, such as an inverter, a memory cell, a NAND gate, and a NOR gate. In one configuration, a CMOS inverter is controlled by four clock signals having four discrete phases. The CMOS inverter optimally includes a CMOS gate transistor pair wherein the semiconductor channels of two ancillary transistors are in series with the semiconductor channels of the CMOS gate transistor pair.
    Type: Grant
    Filed: November 21, 1995
    Date of Patent: October 7, 1997
    Assignee: Lucent Technologies Inc.
    Inventor: Thaddeus J. Gabara
  • Patent number: 5670899
    Abstract: A semiconductor integrated circuit has an integrally formed logic circuit that is controlled by clock signals. The semiconductor integrated circuit includes a clock signal delay device that generates a plurality of clock signals having phases that are shifted from each other by a small amount with respect to a reference clock signal. The logic circuit is divided into a plurality (N number) of circuit blocks so that each of the circuit blocks is controlled by each of the associated plurality of clock signals to reduce noises. Noises in a CMOS integrated circuit are also reduced by controlled reference clock signals. A CMOS integrated circuit includes at least one CMOS gate with an input terminal being commonly connected to gates of a PMOS transistor and an NMOS transistor, and a latch circuit for transmitting data to the input terminal of the CMOS gate by clock signal control.
    Type: Grant
    Filed: November 9, 1995
    Date of Patent: September 23, 1997
    Assignee: Yamaha Corporation
    Inventor: Takayuki Kohdaka
  • Patent number: 5646557
    Abstract: A domino logic circuit includes an evaluation circuit for receiving input signals and performing a logic operation on the input signals, a passgate circuit for controlling the transmission of signals to an output circuit and a feedback latch circuit for holding the output of the evaluation circuit for a predetermined portion of a clock cycle. The output circuit may also include a pair of control transistors to allow the output latching circuit to be turned off during the evaluate portion of the clock cycle thus improving the speed of the domino logic circuit. During the first half of the reset portion of each cycle, the output latching circuit is active and allows the circuit to retain its output state. During the time the passgates are turned off, the evaluate circuit is disconnected and may begin resetting. During the second half of the reset portion of the clocking signal, the passgates open, which allows the output stage to be reset.
    Type: Grant
    Filed: July 31, 1995
    Date of Patent: July 8, 1997
    Assignee: International Business Machines Corporation
    Inventors: Stephen Larry Runyon, Eric Bernard Schorn
  • Patent number: 5642061
    Abstract: An apparatus and method for providing short circuit current free dynamic logic building blocks comprising P-logic and N-logic dynamic domino building blocks having separate clocks for driving the P-logic and N-logic evaluate and pre-charge stages. The P-logic building gates are pre-charged to a zero volt output and upon the transition from high to low on the input line, will provide a high output during the evaluation cycle. Conversely, the N-logic building blocks are pre-charged with a high output level and upon the transition of a low to high input to the building block device, will provide a low output signal during the evaluation period. Both building block types are pre-charged again at the end of the evaluation period to provide an inherently glitch-free dynamic logic device. Separate evaluate and charge clock signals are provided to each of the P-logic and N-logic building blocks which are configured to provide a non-overlapping charge and evaluation cycle.
    Type: Grant
    Filed: April 17, 1995
    Date of Patent: June 24, 1997
    Assignee: Hitachi America, Ltd.
    Inventor: Douglas J. Gorny
  • Patent number: 5621338
    Abstract: A user configurable circuit contains clock logic, a switching element and a data path circuit. Input data is received in the switching element, and the switching element and the data path circuit constitute the entire data path for the circuit. A plurality of user configurable inputs are received to configure the circuit for a particular user application. The clock logic and the switching element implement a logic function that is configurable by the user configurable inputs. The logic function is pre-processed in the clock logic so that minimal delay occurs in the data path. In addition, the propagation delay through the switching element and the register is independent of the user configurable inputs. The user configurable circuit of the present invention has application for use as a macro cell for a programmable logic device permitting the user to configure the circuit as a D-type flip-flop, a T-type flip-flop. In addition, the user selects the polarity for the output circuit.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: April 15, 1997
    Assignee: Cypress Semiconductor Corp.
    Inventors: Lin-Shih Liu, Syed B. Raza, Hagop Nazarian, George M. Ansel, Stephen M. Douglass, Jeffery S. Hunt
  • Patent number: 5587672
    Abstract: A controller chip has dynamic logic which is driven by a suspendable clock. Power is reduced in a standby mode when the clock to the dynamic logic is stopped. However, power is still applied to the dynamic logic in standby mode so that the dynamic logic can be quickly resumed without the delay of re-charging the power-supply capacitances in the dynamic logic. Stopping the clock to dynamic logic can eventually cause loss of data. A more severe problem than data loss is power consumption. When the clock is stopped to dynamic logic, the isolated nodes leak and eventually their voltages change. When their voltages change by more than a transistor threshold voltage then both the p-channel and n-channel transistors in dynamic logic cells can turn on, forming a direct current paths between power and ground. Thus power consumption can increase dramatically in suspend mode. The isolated dynamic nodes of the dynamic logic are instead recharged periodically during suspend mode.
    Type: Grant
    Filed: September 25, 1995
    Date of Patent: December 24, 1996
    Assignee: NeoMagic Corp.
    Inventors: Ravi Ranganathan, Deepraj S. Puar
  • Patent number: 5543735
    Abstract: A latch, connected between an input self-reset dynamic MOS logic circuit and an output self-reset dynamic MOS logic circuit, is provided with clocked interface circuitry to assure proper latching of the state of the input logic in the latch and provides a pulsed output to the output logic circuit. Circuitry is provided to control the self-reset operation of the input logic circuit such that the reset does not occur until a predetermined period of time after the leading edge of the clock pulse latching the state of the input self-reset circuit in the latch. The output of the latch is gated from the latch to the output self-reset circuit under the control of a chopper circuit. The chopper circuit provides a control pulse to gate the state of the latch to the output self-reset circuit a predetermined period of time after the data has been latched. The control pulse has a duration sufficient to assure that the state of the latch is registered in the output self-reset logic.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: August 6, 1996
    Assignee: International Business Machines Corporation
    Inventor: Tin-chee Lo
  • Patent number: 5541536
    Abstract: A circuit for evaluating logic inputs responsive to a reference clock, which circuit includes a first clock terminal for coupling with a first clock, the first clock being delayed from the reference clock by a first frequency dependent delay period. The circuit includes a second clock terminal for coupling with a second clock, the second clock being delayed from the reference clock by a second frequency dependent delay period. The inventive circuit further includes a first circuit stage, which includes a pulse generation circuit coupled to both the first clock terminal and the second clock terminal. In one embodiment, the first circuit stage further includes an output terminal, an evaluation device coupled to the output terminal and the pulse generation circuit. The first circuit stage also includes a precharge device coupled to the output terminal, a third clock terminal, and a first logic level, the third clock being delayed from the reference clock by a third frequency dependent delay period.
    Type: Grant
    Filed: May 24, 1995
    Date of Patent: July 30, 1996
    Assignee: Sun Microsystems, Inc.
    Inventor: Sathyanandan Rajivan
  • Patent number: 5517136
    Abstract: An opportunistic time-borrowing domino logic includes a domino pipeline having a plurality of logic gates coupled in series and controlled by first, second, third and fourth clock signals. The first domino gate in a half-cycle is clocked by either the first or the second clock signals, wherein the last domino gate in a half-cycle is clocked by either the third or the fourth clock cycles. The second clock signal is an inverse of the first clock signal, and the third and fourth clock signals have local delayed clock phases in which the falling edges of the third and fourth clock signals are delayed relative to the falling edges of the respective first and second clock signals. In a first half-cycle, a first type of domino gate is controlled by the first clock signal, with subsequent domino gates of the same type being controlled by the third clock signal.
    Type: Grant
    Filed: March 3, 1995
    Date of Patent: May 14, 1996
    Assignee: Intel Corporation
    Inventors: David Harris, Sunny C. Huang, James Nadir, Ching-Hua Chu, Jason C. Stinson, Alper Ilkbahar
  • Patent number: 5510732
    Abstract: A digital system including a synchronizer circuit which significantly reduces the occurrence of metastability conditions during data transfer between a first digital subsystem and a second digital subsystem is disclosed. The synchronizer circuit includes a master synchronizer cell and a slave synchronizer cell for handling data transfer from the first subsystem to the second subsystem. Each synchronizer cell includes a signal node, a discharge node, a first discharge patch and a second discharge path, both coupled between the signal node and the discharge node, and a control element coupled to the first discharge path and the second discharge path. The control element selectively activates the first discharge path and the second discharge path in response to an input signal.
    Type: Grant
    Filed: August 3, 1994
    Date of Patent: April 23, 1996
    Assignee: Sun Microsystems, Inc.
    Inventor: Bal S. Sandhu
  • Patent number: 5508639
    Abstract: The invention is a power conserving clock driver circuit operative where a differential pair of clock (clock+ and clock-) signals are desired. The circuit responds to transitions in both clock signals to turn off the clock driver transistors (M1P,M1N) (M2N, M2P) for a period of time. During that period of time, a pass gate configuration (M3N, M3P) is conductive. When this occurs, the charge on one of the capacitive loads C.sub.L1 or C.sub.L2 is transferred through the inductor L.sub.c. In this fashion, part of the charge on one of the capacitive loads is transferred directly to the other capacitive load thereby conserving power. The time period during which this power transfer occurs is the time for one half cycle at the natural resonant frequency of the circuit comprised of L.sub.c, C.sub.L1 and C.sub.L2.
    Type: Grant
    Filed: January 13, 1995
    Date of Patent: April 16, 1996
    Assignee: Texas Instruments Incorporated
    Inventor: John W. Fattaruso
  • Patent number: 5508640
    Abstract: A first transistor is connected to a second transistor so that the first and second transistors may be initially biased in a non-conducting state when a first node is at a first voltage potential and a second node is at a second voltage potential. A potential altering circuit selectively alters the voltage potential at the first and second nodes, causes the first and second transistors to be in a conducting state for accelerating a voltage transistion at the first and second nodes toward final values, and maintains the first and second nodes at their final voltage potentials for implementing a desired Boolean function.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: April 16, 1996
    Assignee: Intergraph Corporation
    Inventors: Hamid Partovi, Donald A. Draper
  • Patent number: 5506520
    Abstract: An energy saving clock signal generator is disclosed including a source of multi-phase waveform signals, a shift register, and a matrix switch. The waveform source provide four, six or more waveform signals to the shift register and the matrix switch. A number of progressive pulses N.sub.pp which are an integer multiple of the number of waveform signals are applied from the shift register to the matrix switch. The matrix switch responds to the waveform signals and the progressive pulse signals to produce a number of output clock signals which may be used to drive adiabatic logic circuits.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: April 9, 1996
    Assignee: International Business Machines Corporation
    Inventors: David J. Frank, Paul M. Solomon
  • Patent number: 5502403
    Abstract: A user configurable circuit contains clock logic, a switching element and a data path circuit. Input data is received in the switching element, and the switching element and the data path circuit constitute the entire data path for the circuit. A plurality of user configurable inputs are received to configure the circuit for a particular user application. The clock logic and the switching element implement a logic function that is configurable by the user configurable inputs. The logic function is pre-processed in the clock logic so that minimal delay occurs in the data path. In addition, the propagation delay through the switching element and the register is independent of the user configurable inputs. The user configurable circuit of the present invention has application for use as a macro cell for a programmable logic device permitting the user to configure the circuit as a D-type flip-flop, a T-type flip-flop. In addition, the user selects the polarity for the output circuit.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: March 26, 1996
    Assignee: Cypress Semiconductor Corp.
    Inventors: Lin-Shih Liu, Syed B. Raza, Hagop Nazarian, George M. Ansel, Stephen M. Douglass, Jeffery S. Hunt
  • Patent number: 5495189
    Abstract: A non-overlap signal generation circuit for a semiconductor memory device which generates two non-overlapped output signals of complementary logic levels with respect to one input signal. The circuit comprises first and second data paths. The first data path includes a first transistor for transiting a first output node from logic "0" to logic "1" when the input signal is transited from logic "0" to logic "1", whereas from logic "1" to logic "0" when the input signal is transited from logic "1" to logic "0", a first inverter for inverting the input signal, and a second transistor for transiting the first output node from logic "1" to logic "0" in response to an output signal from the first inverter.
    Type: Grant
    Filed: December 22, 1994
    Date of Patent: February 27, 1996
    Assignee: Goldstar Electron Co., Ltd.
    Inventor: Hong S. Choi
  • Patent number: 5453707
    Abstract: A single-phase clock and an output signal of a second delay circuit are inputted to a first NAND gate and a first NOR gate. The output signal of the first NAND gate is inputted to a gate of a first PMOS transistor of a first clock driver. The output signal of the first NOR gate is inputted to a gate of a first NMOS transistor of the first clock driver. Meanwhile, an inverted clock outputted from an inverter and an output signal of a first delay circuit are inputted to a second NAND circuit and a second NOR circuit. The output signal of the second NAND gate is inputted to a gate of a second PMOS transistor of a second clock driver. The output signal of the second NOR gate is inputted to a gate of a second NMOS transistor of the second clock driver.
    Type: Grant
    Filed: January 6, 1994
    Date of Patent: September 26, 1995
    Assignee: NEC Corporation
    Inventors: Koichi Hiratsuka, Hiroshi Hikichi
  • Patent number: 5442308
    Abstract: A dynamic decoder stores decoded signals in latch circuits for producing output signals, and the latch circuits are disabled after storing the decoded signals so that the output signals are free from undesirable level change of the decoded signals due to leakage between the dynamic decoding operations.
    Type: Grant
    Filed: February 2, 1994
    Date of Patent: August 15, 1995
    Assignee: NEC Corporation
    Inventor: Hisashi Fujiwara
  • Patent number: 5440250
    Abstract: A clock-generating circuit for logic circuits with clock-controlled decoupling stages includes an interlock circuit which, in an interlocking mode, sets the outputs of the clock-generating circuit and thus, the clock lines, to an interlocking potential, thereby causing the decoupling stages to be placed into a shunt-current-free operating state.
    Type: Grant
    Filed: May 26, 1994
    Date of Patent: August 8, 1995
    Assignee: Deutsche ITT Industries GmbH
    Inventor: Michael Albert
  • Patent number: 5434520
    Abstract: Clocking systems and methods of the present invention use two or more different clock signals for respective groups or stages of self-timed dynamic (or mousetrap) logic gates. Each clock signal defines a precharging time interval and an evaluation time interval for its respective group or stage of self-timed dynamic logic gates. Using the two or more different clock signals, pipelining of the groups or stages of the self-timed dynamic logic gates can be performed.
    Type: Grant
    Filed: May 19, 1992
    Date of Patent: July 18, 1995
    Assignee: Hewlett-Packard Company
    Inventors: Jeffry D. Yetter, Robert H. Miller, Jr.
  • Patent number: 5402012
    Abstract: The present invention relates to an implementation of domino logic using a logic cell which is not limited to the use of positive logic functions, and which can be implemented using MOS technology. A significant feature of the present invention relates to use of a single clock cycle to generate separate clock phases for a first function (e.g., carry function of a full-adder logic cell) and a second function (e.g., sum function in the full-adder logic cell). The separate clock phase used to gate the second function corresponds to a delayed version of the clock phase used to gate the first function, wherein the clock delay corresponds to a delay through the first function. In one exemplary embodiment, the delay can be made equal to that of the first function by using circuitry identical to that of the first function to create the delay period.
    Type: Grant
    Filed: April 19, 1993
    Date of Patent: March 28, 1995
    Assignee: VLSI Technology, Inc.
    Inventor: Steven D. Thomas
  • Patent number: 5378942
    Abstract: A CMOS dynamic logic structure has a plurality of logic gates, and the logic gates includes type-1 and type-3 logic gates alternately connected with each other. Each logic gate is separated into a function unit and a driver unit. The function unit has a PMOS precharge transistor, and a logic tree block stacked with the PMOS precharge transistor. The driver unit has an NMOS evaluation transistor, and the NMOS evaluation transistor and the PMOS precharge transistor of the previous-stage logic gate is controlled by an identical clock in order not to be turned on simultaneously.
    Type: Grant
    Filed: June 3, 1993
    Date of Patent: January 3, 1995
    Assignee: National Science Council
    Inventors: Chung-Yu Wu, Kuo-Hsing Cheng