Accelerating Switching Patents (Class 326/17)
  • Patent number: 6031388
    Abstract: A circuit style, which may be employed in fast, area-efficient, flexible programmable interconnect architectures, or in logic circuits, is disclosed. In one embodiment, a plurality of postcharged speed-up circuits, each having a single network node, is connected to the intermediate nodes of a programmable interconnect architecture. Each speed-up circuit monitors the logic level on the network node. When a circuit detects a substantial change in logic level, away from the stand-by level, it temporarily enforces that change by connecting its network node to the signaling logic level. Thus, on each node, a low-impedance enhancement of the signal driving the node temporarily appears. This causes the potential on neighboring nodes, connected through conducting programmable switches, to change towards the signaling level, and their speed-up circuits in turn temporarily enforce the new level.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: February 29, 2000
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventor: Ivo Dobbelaere
  • Patent number: 6016064
    Abstract: There is a parallel-connected circuit of a first PMOS transistor P1 having its gate connected to a first input terminal IN1 and a second PMOS transistor P2 having its gate connected to a second input terminal IN2, and a first series-connected circuit of a first NMOS transistor N1 having its gate connected to the first input terminal IN1 and a second NMOS transistor N2 having its gate connected to the second input terminal IN2, and there is a second series-connected circuit of a third PMOS transistor P3 having its gate connected to the first input terminal IN1 and a fourth PMOS transistor P4 having its gate connected to the second input terminal IN2, which is provided between the first power supply and output terminal, this being connected in parallel with the parallel-connected circuit of the first PMOS transistor P1 and the second PMOS transistor P2.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: January 18, 2000
    Assignee: NEC Corporation
    Inventor: Takanori Saeki
  • Patent number: 6002270
    Abstract: A synchronous differential logic system is provided for implementation of pipelined computational structures capable of hyperfrequency operation. An individual logic circuit has a differential cascode switch and a synchronous sense amplifier which operates as a latch. A plurality of differential inputs are connected to the differential cascode switch which produces complementary signals at first and second nodes. The cascode switch is connected to the synchronous sense latch which provides complementary output signals of the logic circuit. The synchronous sense latch comprises an equalization transistor and two cross-coupled inverters, each connected to first and second power supply buses. The equalization transistor is connected to the first and second outputs, of the logic gate and to a global system clock.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: December 14, 1999
    Assignee: Spaceborne, Inc.
    Inventor: Constantin C. Timoc
  • Patent number: 6002272
    Abstract: A domino logic circuit includes a clocked precharge stage coupled to a positive voltage rail with the precharge stage having an input. An evaluation network adapted to receive at least one input is coupled between the precharge stage and a common voltage rail. A static CMOS stage is coupled to the positive voltage rail, and includes an input and an output, the input being coupled to a junction formed by the precharge stage and the evaluation network. A negative voltage rail is coupled to the static CMOS stage to precharge the output negative.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: December 14, 1999
    Assignee: Intel Corporation
    Inventors: Dinesh Somasekhar, Vivek De
  • Patent number: 5999019
    Abstract: A CMOS Critical Voltage Transition Logic device which reduces propagation delays in a circuit by preconditioning the voltage outputs of each stage of the circuit to a critical voltage value which is between the logic high and logic low values for the circuit. The transition time to achieve either the high or low logic output states which is responsive to the input signal from the previous stage is reduced due to the preconditioning. Each stage is synchronously clocked in order to achieve the preconditioned state in each stage before processing the input signal for the previous stage. This unique switching characteristic greatly reduces the propagation delay in the circuit.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: December 7, 1999
    Assignee: The Research Foundation of State University of New York
    Inventors: Zhu Zheng, Bradley S. Carlson
  • Patent number: 5982198
    Abstract: A logic circuit includes a potential coupled to a node and a first transistor coupled between a first input and the output with its gate coupled to the node. At least a second transistor is coupled between the node and ground with its gate coupled to a second input. At least a third transistor is coupled between the output terminal and ground with its gate connected to the second input.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: November 9, 1999
    Assignee: Honeywell Inc.
    Inventor: David E. Fulkerson
  • Patent number: 5977789
    Abstract: A logic device that allows the implementation of a fast-switching logic gate is described. One implementation of the logic device includes an output node and a reference node electrically isolated from one another by a transmission gate. During a first period of time, the nodes are charged to complementary logic levels. During a second period of time, the transmission gate is enabled, allowing the charge on the nodes to be redistributed. A pair of complementary input terminals are connected to the reference and output nodes, such that if the input terminal connected to the output node is at the same logic level as the output node during the first period, then the voltage level of the output node is pulled back from its redistributed state to its original state.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: November 2, 1999
    Assignee: Intel Corporation
    Inventor: Eric S. Gayles
  • Patent number: 5977795
    Abstract: A differential transistor pair is used for a Low Voltage Transistor-Transistor Logic (LVTTL) input buffer to provide an input buffer for a modified and enhanced LVTTL specification. The differential input buffer accurately detects high and low voltages which are respectively lower and higher than existing specified LVTTL voltage levels, yet provides output voltages that are representative of intended logic levels. This provides the ability to use the improved input buffer with existing drivers at higher frequencies where the voltage swing provided by the existing drivers do not produce as large a voltage swing as that required by existing LVTTL specifications.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: November 2, 1999
    Assignee: Micron Technology, Inc.
    Inventor: Terry R. Lee
  • Patent number: 5973512
    Abstract: A buffer having an output slew rate which is relatively insensitive to loading and supply voltage. The output buffer includes an output node, a first half-circuit and a second half-circuit. The first half-circuit is for slewing the output node from a first voltage to a second voltage. The first half-circuit includes a first output transistor connected between the output node and a second voltage reference node, a first switching device connected from a gate of the first output transistor to the second voltage reference node, a second switching device connected from the gate of the output transistor to a first node, a first current source connected from a first voltage reference node to the first node, and a first capacitor connected from the output node to the first node. The second half-circuit is for slewing the output node from the second voltage to the first voltage.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: October 26, 1999
    Assignee: National Semiconductor Corporation
    Inventor: Alan J. Baker
  • Patent number: 5969542
    Abstract: An improved gate oxide protected level shifter is provided which has a higher speed of operation than is traditionally available. The level shifter includes a first capacitor coupled between a first output terminal and the input of an inverter and a second capacitor coupled between a first node and the output of the inverter. As a result, the speed of the transitions at the gates of the pair of cross-coupled P-channel MOS transistors is increased several times.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: October 19, 1999
    Assignee: Advanced Micro Devices, Inc.
    Inventors: Reading Maley, Albrecht Schoy
  • Patent number: 5966042
    Abstract: A current output circuit comprises a current driver that is switchably connected across two output nodes by a switching assembly and having a switchable shunt resistor connected across the current driver. The switchable shunt resistor may be switched between a non-conducting state and a resistive conducting state. In a first data state, the current driver is connected to the output nodes by the switching assembly and the switchable shunt resistor is non-conducting so that the supplied current will flow through a load attached to the output nodes. In a second data state, the current driver is disconnected from the output nodes and the switchable shunt resistor is in a resistive conducting state. In this state the current bypasses the load and is diverted through the switchable shunt resistor. Several current drivers with appropriate switching arrangements and one or more switchable shunt resistors may be provided to allow for asymmetric current outputs in various data states.
    Type: Grant
    Filed: September 29, 1997
    Date of Patent: October 12, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Wayne E. Werner, Thaddeus John Gabara, Bijit Thakorbhai Patel
  • Patent number: 5952848
    Abstract: The input buffer of a low-voltage technology integrated circuit (IC) has a buffer transistor adapted to receive an input signal at the gate of the input buffer. The channel nodes of the input buffer are connected to other circuitry (e.g., the low-voltage bias voltage and a current source). With such an input buffer, the low-voltage circuit can safely receive a relatively high input voltage. As such, the low-voltage circuit can be interfaced to and safely operated in conjunction with relatively high-voltage technology circuitry. In one implementation, IC circuitry of existing 5V technology can be safely used with IC circuitry of a new 2.5V technology having an input buffer of the present invention.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: September 14, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Bernard L. Morris
  • Patent number: 5942916
    Abstract: A logic circuit has a signal line for transmitting a digital signal as a voltage level and a loop circuit serving as a memory unit for storing the digital signal. Input and output terminals of the loop circuit are connected to the signal line. The loop circuit is a partial circuit having an even number (at least two) of signal inverters each having capacitive input load. At least one of the input and output terminals of the loop circuit is connected to an electric resistor. The loop circuit has a time constant T that is determined by the product RC of the resistance R of the resistor and the intentional and parasitic capacitance C of the signal inverters. The time constant T has a given relationship with the operation frequency of the logic circuit. The resistance R and capacitance C form a low-pass filter. The logic circuit provides different equivalent circuits in high and low frequency regions above and below the cutoff frequency of the low-pass filter.
    Type: Grant
    Filed: August 14, 1996
    Date of Patent: August 24, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Gensoh Matsbara, Chikahiro Hori
  • Patent number: 5926050
    Abstract: A digital system includes apparatus for propagating falling and rising edges of a digital signal through two separate data paths each optimized to maximize propagation of one edge of the signal. The first data path is structured to propagate the first transition (e.g., falling edge) of the digital signal with a delay less than that experienced by the second transition (rising edge); and the second data path is structured to propagate the second transition with much less delay than that experienced by the first data transitions. The outputs of the two data paths are applied to a combining circuit, and put together to form a final representation of the digital signal to use the first and second state transitions as propagated by the apparatus.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: July 20, 1999
    Assignee: Townsend and Townsend and Crew LLP
    Inventor: Robert J. Proebsting
  • Patent number: 5926039
    Abstract: An active load (12) is provided for an N channel logic network (10). The active load (12) includes a P channel device (28) coupled to the output node (14) of the N channel network (10). A clock circuit (16) of the active load (12) determines whether the N channel network (10) is in a steady state or a switching mode. If the N channel network (10) is in a switching mode, an intermediate voltage level, V.sub.bias, is applied at the gate of the P channel device (28) to facilitate fast switching at the output node (14) with low quiescent power consumption and without compromising compact semiconductor layout.
    Type: Grant
    Filed: March 19, 1997
    Date of Patent: July 20, 1999
    Assignee: Texas Instruments Incorporated
    Inventors: Shivaling S. Mahant-Shetti, Kameshwar C. Rao
  • Patent number: 5926037
    Abstract: A buffer circuit which can solve a problem of a conventional buffer circuit in that high speed data transfer is hindered because of parasitic capacitance of signal lines, which has an affect on the discharge time of inverters in a latch circuit of the buffer circuit, when the buffer circuit changes its state from a first term (non-transfer mode) to a second term (transfer mode). The buffer circuit solves this problem by pouring a current, which flows thereinto from a first signal line, into ground through a first PMOS transistor, a first NMOS transistor and a third NMOS transistor, and by pouring a current, which flows thereinto from a second signal line, into the ground through a second PMOS transistor, a second NMOS transistor and the third NMOS transistor.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: July 20, 1999
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Fumiki Sato, Kouichi Fujita
  • Patent number: 5910734
    Abstract: A translator includes an initial circuit device configured to charge a translator output to a first voltage level in response to a change in an input signal. The translator further includes a sensing device configured to detect the output's potential approaching the first voltage level and smoothly shift charging functions over to a secondary circuit device, which will continue to charge the output up to a second voltage level.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: June 8, 1999
    Assignee: Micron Technology, Inc.
    Inventor: Troy Manning
  • Patent number: 5909127
    Abstract: This invention provides a circuit and method to replace the passive resistive or statically biased active load devices with dynamically biased active load devices. This allows the load devices to present an effective load which varies depending on the state of the circuit output. The effective load and the time rate of change of the effective load can be dynamically optimized to improve circuit performance with changing conditions. The effective load is varied according to the state of the circuit by the use of time-delayed negative feedback. The biasing of the load devices is also capable to control the logic swing of the circuit. A bias generating circuit employing a dynamically biased active load is described. This provides a method for a family of logic circuits, especially CML circuits, to operate at low voltage and low power at high switching speeds, having symmetrical rise and fall times and well defined logic signal swings.
    Type: Grant
    Filed: February 14, 1996
    Date of Patent: June 1, 1999
    Assignee: International Business Machines Corporation
    Inventors: Dale Jonathan Pearson, Scott Kevin Reynolds
  • Patent number: 5898677
    Abstract: Signal area efficiency in integrated circuit designs is improved by increasing the information efficiency of signal wiring on an integrated circuit. Candidate signals are selected for combination by prioritizing signals according to length of travel, travel path, and information content. Signals with low information content and with greater distance between endpoints make poor utilization of fixed wiring and provide the best candidates for improvement. Candidate signals which travel similar (substantially parallel) paths from point to point across the integrated circuit are combined to improve chip area utilization efficiency. A variety of techniques are described for combining low-information-content signals onto a small number of wires, transmitting them over the small number of wires, and re-expanding them at their destination. Assuming that the combining/expanding circuitry occupies less space than the point-to-point wiring which would otherwise be required, there is a net reduction in chip area.
    Type: Grant
    Filed: January 13, 1997
    Date of Patent: April 27, 1999
    Assignee: LSI Logic Corporation
    Inventors: Richard Deeley, Carlos Dangelo
  • Patent number: 5898315
    Abstract: The present invention concerns a circuit and method for improving the data access times across boundary reads between cascaded buffers, such as FIFOs, that are connected to a common data output bus. The circuit allows read accesses within a cascaded buffer system to have similar access speeds, i.e., a boundary read is not noticeably slower or faster than any other non-boundary read access from an individual buffer in the system. The circuit may not adversely affect the data sheet or operating system parameters, and imposes minimal chip real estate constraints.
    Type: Grant
    Filed: May 17, 1996
    Date of Patent: April 27, 1999
    Assignee: Cypress Semiconductor Corp.
    Inventor: Roland T. Knaack
  • Patent number: 5896043
    Abstract: A level shift circuit includes first and second operation circuits, a bias circuit, and a current control circuit. The first and second operation circuits include high-voltage transistors and low-voltage transistors connected in series. The high-voltage transistors are controlled according to a potential at the interconnection point between the low-voltage and high-voltage transistors of opposite operation circuits. The bias circuit is provided in a one-to-one correspondence with the operation circuits and connected to the low-voltage transistors in series to activate the transistors in the stationary on state and decrease currents flowing into the transistors to a stationary current. The current control circuit connects to the bias circuit in parallel to increase the currents just after the low-level transistors are turned on to a high peak current. The low-voltage transistors are turned on/off alternately in response to the state transition of an input signal.
    Type: Grant
    Filed: January 16, 1997
    Date of Patent: April 20, 1999
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Naoki Kumagai
  • Patent number: 5886541
    Abstract: A circuit combines the functions of a logic gate and a latch to lower steady state power dissipation during gate operation. The circuit operates in two modes: a flow-through mode and a latched mode. In the flow-through mode, a gate portion which receives one or more digital input signals implements the complement of a desired Boolean logic function on the input signals and provides an internal signal. The gate portion may have a steady-state power dissipation while providing the internal signal. An inverter in a latch portion of the circuit inverts the internal signal to generate an output signal which represents the desired logical combination of the input signals. The inverter provides the output signal with a full-range CMOS voltage. In latched mode, the gate portion is disabled to stop the steady-state power dissipation while the latch portion of the circuit preserves the desired output signal.
    Type: Grant
    Filed: August 5, 1996
    Date of Patent: March 23, 1999
    Assignee: Fujitsu Limited
    Inventor: Creigton Asato
  • Patent number: 5869984
    Abstract: An output buffer circuit includes a portion for receiving an input signal in which a level thereof is changed from a high level to a low level and vice versa, and a circuit block for operating based on the input signal received by the portion and for outputting an output signal in which a level thereof is changed from a high level to a low level and vice versa in response to level transition of the input signal, the circuit block including a circuit arrangement of a plurality of FETs for temporarily lowering an output resistance of the circuit block in level transition of the output signal.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: February 9, 1999
    Assignee: Fujitsu Limited
    Inventor: Satoshi Eto
  • Patent number: 5856746
    Abstract: A "slow" signal is not sent across chip to be combined with combinatorial logic, but rather, the logic with which it would be combined is partitioned such that there are two outputs, one if the "slow" signal would be true and a second if the "slow" signal would be false. Both of these outputs are then provided to a multiplexer. The original "slow" signal selects the correct signal, thus saving the interconnect time delay. The concepts also apply to combinations of multiple "slow" signals.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: January 5, 1999
    Assignee: Sun Microsystems, Inc.
    Inventor: Bruce E. Petrick
  • Patent number: 5852367
    Abstract: A level shifting circuit operating at low power with minimal signal delays. The circuit employs high capacitance diodes to shift signals from a first signal level to a second higher or lower signal level. The capacitance is obtained by either providing a discrete capacitor shunt across the diode or by using diode connected transistors. Diode connected transistors are biased to provide the necessary capacitance. A pair of high capacitance diode level shifters is used as a differential pair level shifter by connecting the reference resistors to a common reference potential.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: December 22, 1998
    Assignee: International Business Machines Corporation
    Inventors: David William Boerstler, Edward Baxter Eichelberger, Gary Thomas Hendrickson, Charles Barry Winn
  • Patent number: 5841300
    Abstract: The present invention is intended to provide a conventional circuit apparatus which is highly tolerant to noises and operates at a higher speed than a completely complementary static CMOS circuit. To achieve this, circuit apparatus according to the present invention is provided with a plurality of CMOS static logic circuits which are series-connected and potential setting means which is connected to the output parts of these logic circuits and sets the outputs of the output parts to a low level in synchronization with a clock signal, thus propagating signals by operation of the NMOS circuit. In other words, a signal propagation delay occurs only when the N-type logic block conducts. Therefore circuit operation is speeded up and .alpha. particle noise and noises due to charge redistribution effect or leakage current can be prevented.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: November 24, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Fumio Murabayashi, Tatsumi Yamauchi, Takashi Hotta, Hiromichi Yamada
  • Patent number: 5841297
    Abstract: A circuit arrangement 10 for driving an MOS field-effect transistor QO allocated to the supply circuit KO of an electrical load R.sub.L contains a charging circuit K1 and a discharging circuit K2, which can be alternatively connected to the MOS field-effect transistor QO. A sensing circuit K3 supplies the measuring signal S.sub.M typical of gate-source voltage U.sub.GS of the MOS field-effect transistor QO, via which the internal resistance of the charging or discharging circuit K1, K2 and/or a current I.sub.a impressed upon these circuits K1, K2, in the sense of a positive feedback, is controlled, in such a way that the resulting time constant, according to which the input capacitance of the MOS field-effect, transistor QO is charged or discharged, becomes smaller during the transition of the MOS field-effect transistor QO from the off state to the conductive state and larger during the transition from the conductive to the off-state.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: November 24, 1998
    Assignee: Texas Instruments Deutschland GmbH
    Inventors: Erich Bayer, Konrad Wagensohner
  • Patent number: 5828234
    Abstract: The pulsed reset single phase dynamic logic of the present invention reorders the conventional modes of operation such that in a single cycle of operation of a domino logic circuit, reset occurs first, followed sequentially by gap2, evaluation and gap1. To reset each domino stage prior to evaluating, a reset pulse is propagated to each domino stage, with an evaluate signal arriving at each stage as the reset pulse is ending. The circuit configuration of the present invention creates a different, but shorter and easier to manage set of race conditions. The present invention permits the creation of faster and more robust circuit designs.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: October 27, 1998
    Assignee: Intel Corporation
    Inventor: Milo David Sprague
  • Patent number: 5828235
    Abstract: A semiconductor integrated circuit device is composed of logic gates each provided with at least two MOS transistors. The logic gates are connected to a first potential point and a second potential point. The semiconductor integrated circuit device includes a current control device connected between the logic gate and the first potential point and/or between the logic gate and the second potential point for controlling a value of a current flowing in the logic gate depending on an operating state of the logic gate. The circuit can be used in devices that cycle in operation between high and low power consumption modes, such as microprocessors that have both an operation mode and a low power back-up or sleep mode used for power reduction.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: October 27, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masashi Horiguchi, Kunio Uchiyama, Kiyoo Itoh, Takeshi Sakata, Masakazu Aoki, Takayuki Kawahara
  • Patent number: 5825208
    Abstract: According to the present invention, a domino CMOS logic circuit having a plurality of stages for evaluating logic signals is provided. In one embodiment, the domino CMOS logic circuit includes at least one stage which has a logic block that includes a plurality of logic devices, inputs and outputs, and a precharge/evaluate circuit. In a more specific embodiment, the circuit includes a first transistor having a source connected to a supply voltage, a gate connected to a delayed clock signal, and a drain, a second transistor having a source connected to the drain of the first transistor, a gate connected to a clock signal, and a drain connected to the outputs of the logic block.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: October 20, 1998
    Assignee: International Business Machines Corporation
    Inventors: Howard Lawrence Levy, Salim Ahmed Shah
  • Patent number: 5825198
    Abstract: This invention is to reduce the power dissipation of a semiconductor integrated circuit chip when it is operated at an operating voltage of 2.5 V or below. To achieve the object, a switching element is provided in each circuit block within the semiconductor integrated circuit chip. The constants of the switching element are set so that the leak current in the switching element of each circuit block in their off-state is smaller than the subthreshold current of the MOS transistors within the corresponding circuit block. The active current is supplied to the active circuit blocks, while the switching elements of the non-active circuit blocks are turned off. Thus, the dissipation currents of the non-active circuit blocks are limited to the leak current value of the corresponding switching elements. As a result, the sum of the dissipation currents of the non-active circuit blocks is made smaller than the active current in the active circuit blocks.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: October 20, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Takeshi Sakata, Kiyoo Itoh, Masashi Horiguchi
  • Patent number: 5821769
    Abstract: A MOSFET circuit achieving high speed operation and low power consumption for a wide supply voltage range. MOSFET circuits are connected between a low threshold voltage CMOS circuit and a supply voltage and ground, as a power controller for switching power supply in response to sleep/active modes. High threshold voltage MOSFETs in the MOSFET circuits are gate biased by low threshold voltage MOSFETs, thereby preventing a current from flowing across the backgate terminal and the source terminal.
    Type: Grant
    Filed: April 18, 1996
    Date of Patent: October 13, 1998
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventor: Takakuni Douseki
  • Patent number: 5818259
    Abstract: A BiCMOS logic circuit having greater drive and speed at low voltage is provided. The logic circuit includes a switching device which allows the pull-down device of the logic circuit to be driven directly by an input signal without first having to switch a MOS device. The switching device conducts current between the input terminal of the logic device and the pull-down device when the output signal equals a certain value.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: October 6, 1998
    Assignee: Philips Electronics North America Corporation
    Inventor: Brian Clark Martin
  • Patent number: 5818280
    Abstract: A shifter receives a multi-logic state input signal and generates a multi-logic state output signal responsive to switches in logic state of the input signal and whose voltage level is shifted with respect to the input signal. A feedback circuit feeds a signal derived from the output signal back to the shifter to precondition the shifter so that the speed of the output signal switching is accelerated.
    Type: Grant
    Filed: December 11, 1995
    Date of Patent: October 6, 1998
    Assignee: International Business Machines Corporation
    Inventor: Douglas Ele Martin
  • Patent number: 5818257
    Abstract: An interface circuit for coupling the output of an integrated circuit designed for a relatively low supply voltage to a circuit designed to operate at a higher supply voltage employs a cascoded architecture and makes use of two purposely derived reference voltages. The circuit comprises a level rising stage, an output buffer stage (off chip driver stage), an overdrive stage for the pull-up device of the output buffer and a drain follower stage, the pull-up element of which is driven by a second output node of the level rising stage and the pull-down element of which is driven by the inverted input data stream.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: October 6, 1998
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventor: Nuccio Villa
  • Patent number: 5818260
    Abstract: A driver for providing binary signals from a data system to a transmission line includes a data input node and an output transistor coupled between a data output node and ground. The output transistor has a gate, a source and a corresponding gate-source voltage therebetween. A first transistor is coupled to the gate of the output transistor and is responsive to signals applied to the input node. It conducts a discharge current from the gate of the output transistor for discharging the gate of the output transistor to reduce its gate-source voltage. A clamping circuit clamps the gate-source voltage of the output transistor to a first voltage level above ground to prevent the discharge current from reducing the, gate-source voltage of the output transistor to ground.
    Type: Grant
    Filed: April 24, 1996
    Date of Patent: October 6, 1998
    Assignee: National Semiconductor Corporation
    Inventor: James R. Kuo
  • Patent number: 5815008
    Abstract: Negative-resistance resonant tunnel diodes (RTDs) perform a complete set of logic functions with a single basic configuration. Inputs feed through Schottky diodes to a transfer RTD coupled to a clocked latch having two RTDs in series. Cascaded gates are driven synchronously by multiple clock phases or by asynchronous event signals. An XOR configuration also provides logical inversion.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: September 29, 1998
    Assignee: Mayo Foundation for Medical Education and Research
    Inventors: William Williamson, III, Barry Kent Gilbert
  • Patent number: 5804989
    Abstract: In a logic circuit including a NAND type or a NOR type decoder, a p-MOS type transistor for precharge or an n-MOS type transistor for discharge is connected to a common node. The transistor allows precharge or discharge to be completed in a short period of time by promoting the charging or discharging of stray capacitances. Therefore, the circuit reduces the period of time necessary for the decoder to produce a high level output or a low level output.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: September 8, 1998
    Assignee: NEC Corporation
    Inventor: Fumihiko Sato
  • Patent number: 5798658
    Abstract: This invention relates to source-coupled logic (SCL) which is a functional derivative of emitter-coupled logic (ECL). ECL is widely recognized as having the characteristics of high speed (low propagation delay) and low power supply noise generation. The SCL of the prior art succeeds at maintaining and improving the low noise characteristics of this architecture but does not fulfill the promise of high speed that one would expect from a current-mode logic. In addition, it uses a differential form of logic that is not as flexible and easy-to-use as a reference controlled or "single-ended" logic. The SCL disclosed here has the desired high speed properties and maintains the ease of use that is a property of reference controlled ECL. In addition, the reference controlled SCL of this invention provides new capabilities that make it even more flexible than ECL in generating logical switching functions.
    Type: Grant
    Filed: October 16, 1996
    Date of Patent: August 25, 1998
    Inventor: Paul M. Werking
  • Patent number: 5793226
    Abstract: A data output buffer circuit for a semiconductor memory device operates with two separate power supplies and prevents malfunctions caused by the sequence in which the power supplies are energized. At lease one discharge transistor is used to remove charge from the gate of one or more NMOS push-pull transistors in an output buffer which can be floating in a charged state if one of the power supplies is energized before the other. In one embodiment, the gates of two discharge transistors are cross-coupled to the gates of the push-pull transistors to assure that at least one of the push-pull transistors are turned off. In an alternative embodiment, one or more discharge transistors are connected to the gates of at least one push-pull transistor and are controlled by a pulse generator that generates a pulse signal in response to variations in the voltage of the power supply for the push-pull transistors.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: August 11, 1998
    Assignee: Samsung Electronics, Co., Ltd
    Inventors: Hee-Choul Park, Kook-Hwan Kwon
  • Patent number: 5786711
    Abstract: A data output buffer of a semiconductor memory device having a data output driver comprised of a pull-up transistor and a pull-down transistor includes a precharging circuit for precharging a gate terminal of the pull-up transistor of the data output driver to a power supply voltage level. Precharging the output driver reduces the load on the pumping voltage generator. This feature, together with precharging the pumping voltage generator itself, allow clocking the pumping voltage generator at a reduced clock rate to reduce power consumption without compromising operating speed of the memory device.
    Type: Grant
    Filed: June 17, 1996
    Date of Patent: July 28, 1998
    Assignee: Samsung Electronics, Co., Ltd.
    Inventor: Hoon Choi
  • Patent number: 5777491
    Abstract: Performance of a dual cascode voltage switch is improved and floating node effects including charge sharing and ratioing of output voltages are avoided by constituting the true and complement logic trees as pass gates of equal height, preferably limited, where possible, to a single transistor. The logic trees have substantially identical transistor layout configurations and different logic functions are established by selective connection of control and conduction terminals of the pass gates to reference logic level voltages of true and complement input variable signal values.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: July 7, 1998
    Assignee: International Business Machines Corporation
    Inventors: Wei Hwang, Fang-Shi Jordan Lai
  • Patent number: 5767700
    Abstract: A pulse signal transfer unit employing post charge logic, comprising a buffering circuit for transferring data with a specified logic value through a data transfer line, a PMOS transistor for supplying a voltage from a voltage source to the data transfer line to initialize a signal on the data transfer line, and a feedback loop circuit for applying the signal on the data transfer line to the PMOS transistor for one of the first and second time periods in response to an external write drive signal to control the PMOS transistor, the second time period being longer than the first time period. According to the present invention, in the case of accessing read data with a relatively narrow pulse width and write data with a relatively wide pulse width, the pulse signal transfer unit initializes the read data at a relatively high speed and the write data at a relatively low speed to provide a signal with a wider pulse width.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: June 16, 1998
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Jae Jin Lee
  • Patent number: 5763962
    Abstract: A high-voltage semiconductor driving circuit to be instantaneously operated for the duration of an arbitrary pulse width can be effectuated through an extremely simple circuit configuration.The circuit comprises a pulse transformer (2) which receives an input pulse signal and generates a pulse voltage, a diode (3) which conducts the pulse voltage to the capacitive gate electrode of the high-voltage semiconductor switching element (5), and another switching element (4) which is connected in parallel to the diode (3) and adapted to discharge, at the falling of the pulse voltage, the gate capacitance which has been charged at the rising of the pulse voltage.
    Type: Grant
    Filed: July 18, 1996
    Date of Patent: June 9, 1998
    Assignee: ECG Co., Ltd.
    Inventor: Keiichi Tsurumi
  • Patent number: 5764083
    Abstract: A system for clocking self resetting CMOS (SRCMOS) circuits operating at high speed includes a clock generator circuit which produces a first pipeline clock pulse of relatively narrow width from a leading edge of a system clock having a relatively long duration with respect to the first pipeline clock, a number of delay circuits, the time duration of each of the delay circuits being determined by characteristics of evaluation logic in the SRCMOS circuits being clocked, the delay circuits being connected in a serial pipeline fashion such that each subsequent delayed clock pulse overlaps a preceding clock pulse by at least a predetermined minimum time duration. The clocking system also includes a cycle relax mode whereby the clock pulse output of the clock generator circuit may be extended for test or diagnostic purposes.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: June 9, 1998
    Assignee: International Business Machines Corporation
    Inventors: Bang T. Nguyen, Mark Daniel Papermaster, Giao Ngoc Pham, Trang Khanh Ta, Willem Bernard van der Hoeven
  • Patent number: 5760608
    Abstract: A register dump providing enhanced efficiency by using a transmission gate for generating a register word line signal so as to reduce clock loading, and by using a complementary gate for generating a precharged pull-down signal so as to reduce discharge time and register word line capacitive loading.
    Type: Grant
    Filed: October 21, 1996
    Date of Patent: June 2, 1998
    Assignee: Hewlett-Packard Co.
    Inventors: Samuel D. Naffziger, Ricky L. Pettit
  • Patent number: 5754061
    Abstract: A Bi-CMOS circuit includes a first bipolar, a second bipolar transistor and a CMOS control unit for performing switching controls of the first and second bipolar transistors on the basis of an input signal applied to an input terminal and for controlling an output signal output via the output terminal on the basis of the input signal. A turn-OFF unit temporality couples the base of the first bipolar transistor to a low-potential side power supply line on the basis of a current flowing in said control means when the first bipolar transistor is turned OFF, so that the first bipolar transistor can be rapidly turned OFF.
    Type: Grant
    Filed: September 3, 1996
    Date of Patent: May 19, 1998
    Assignee: Fujitsu Limited
    Inventors: Shinzou Satou, Kou Ebihara, Akiyoshi Suzuki, Keisuke Ishiwata, Kouji Miki, Hitoshi Ohmichi, Tamio Miyamura, Masamichi Kamiyama
  • Patent number: 5751651
    Abstract: A main source voltage transmission line for transmitting a source voltage VCH as one power source and a sub source voltage transmission line are provided corresponding to a gate circuit. A resistive element having a high resistance is provided between the main source voltage transmission line and the sub source voltage transmission line. A capacitor comprised of an insulated gate field effect transistor is connected to the sub source voltage transmission line. The gate circuit is operated with a voltage on the sub source voltage transmission line as an operating source voltage. Thus, the voltage on the sub source voltage transmission line can be maintained at a voltage level that balances with a sub-threshold current flowing through the gate circuit, and the voltage on the sub source line can be stably maintained by the capacitor.
    Type: Grant
    Filed: October 23, 1995
    Date of Patent: May 12, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Tsukasa Ooishi
  • Patent number: 5739715
    Abstract: A driver circuit for driving multiple lines with unknown loads uses a high slew rate driver to drive the output during input signal transitions, and uses a termination driver to drive the output during input signal steady state conditions. The high slew rate driver provides rapid transitions, and the terminating driver provides ideal output impedance to maintain the fidelity of the output signal.
    Type: Grant
    Filed: October 31, 1995
    Date of Patent: April 14, 1998
    Assignee: Hewlett-Packard Co.
    Inventor: William Peter Rawson
  • Patent number: 5739700
    Abstract: A method and apparatus is disclosed for outputting a signal responsive to, and shifted in signal level relative to, an input signal level. A driver includes first circuitry outputting a first signal responsive to an input signal, and second circuitry outputting a second signal responsive to the input signal. The first circuitry includes circuitry for substantially shifting the first signal level relative to the input signal and responds more slowly than the second circuitry. The driver output is responsive to both the first and second signals so that the second circuitry improves driver response.
    Type: Grant
    Filed: September 9, 1996
    Date of Patent: April 14, 1998
    Assignee: International Business Machines Corporation
    Inventor: Douglas Ele Martin