Patents Represented by Attorney Irving S. Rappaport
  • Patent number: 5144171
    Abstract: A high-speed differential-feedback cascode sense amplifier includes an output stage and a voltage clamp. The voltage clamp is coupled to a pair of bit-sense lines of a memory system or other sense line source. The output stage is coupled to the output of the voltage clamp for generating an output signal having a logic state determined according to the current difference across the bit-sense lines. The voltage clamp includes a pair of transistors (e.g., cascode transistors) in cascode to a differential-feedback gain stage. Bit-sense lines are coupled to the cascode transistors and the differential-feedback gain stage. The gain stage amplifies the current difference across the bit-sense lines to define feedback voltage signals input to the cascode transistors. The parasitic voltage difference across the bit-sense lines resulting from driving the cascode transistors is small, approximately 3-7 mV for an ECL sense amplifier.
    Type: Grant
    Filed: November 15, 1990
    Date of Patent: September 1, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Jeffrey M. Huard
  • Patent number: 5139966
    Abstract: Low resistance contacts for establishing an electrical pathway to an integrated surface substrate are provided. The pathway is formed by the connection of a p+ doped channel stop region with a p+ doped extrinsic layer. P+ doped polysilicon contacts are positioned on the substrate surface. In one embodiment, a metal silicide layer connects the polysilicon contacts and overlies the p+ doped extrinsic layer.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: August 18, 1992
    Assignee: National Semiconductor Corporation
    Inventors: Rick C. Jerome, Frank Marazita
  • Patent number: 5137838
    Abstract: A P-type buried layer is described for use with planar, silicon, monolithic, epitaxial, PN junction-isolated transistors of PNP conductivity primarily for use in IC construction. The buried layer includes a high concentration of boron and gallium along with germanium, which is in sufficient concentration to inhibit impurity diffusion in the silicon epitaxial layer. This inhibition effect has been found to be sufficient to cause the combination of boron and gallium to act as slow diffusers. The result is that the performance of arsenic and antimony, in the creation of buried layers for NPN transistors. Thus, the performance of NPN transistors can be matched for PNP transistors. This means that an IC can be fabricated so that more nearly equal performance NPN and PNP transistors can be fabricated simultaneously in a common substrate.
    Type: Grant
    Filed: June 5, 1991
    Date of Patent: August 11, 1992
    Assignee: National Semiconductor Corporation
    Inventors: Amolak Ramde, Sheldon Aronowitz
  • Patent number: 5136364
    Abstract: Integrated circuit bonding pads are sealed by a surface passivation coating. The bonding pads are first edge-sealed by means of a first applied passivation coating that overlaps the edges of the bonding pad while leaving the central area uncoated. Then, a sequence of metal layers applied to overlap the open central area of the bonding pad. The layer sequence includes an optional first adherence layer such as aluminum, a barrier metal layer such as titanium-tungsten alloy, and an outer noble metal layer such as gold. Then, a second passivation layer is applied so as to overlap and seal the edges of the sequence of metal layers so as to leave only the central portion of the noble metal layer exposed. Electrical contact to the IC is then made to the exposed noble metal in the conventional manner. With respect to the passivating coatings, either or both can be silicon dioxide overcoated with silicon nitride.
    Type: Grant
    Filed: June 12, 1991
    Date of Patent: August 4, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Robert C. Byrne
  • Patent number: 5130576
    Abstract: An ECL to CMOS translator for BiCMOS circuits. The circuit has a first bipolar transistor which switches the translator from a quiescent state to an active state in the presence of an ECL high level signal. An amplifier driving an NMOS capacitive load amplifies this signal to CMOS levels. Two clock signals reset the circuit to the quiescent state once the ECL high signal has passed. The circuit is kept in the quiescent state by a current source.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: July 14, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Dennis L. Wendell
  • Patent number: 5122681
    Abstract: A synchronous BiCMOS logic circuit which operates between two voltage supplies and has at least one input terminal, an intermediate node and an output terminal is disclosed. The logic circuit is capable of a high speed transition in response to a signal pulse from a first logic state to a second logic state at the input terminal. The logic circuit has at least one MOS input transistor of a first polarity having a gate electrode connected to the input terminal. The MOS input transistor is coupled between the first voltage supply and the output node by its source/drain electrodes. A first current supply connected to the output node to the second voltage supply and weakly holds the intermediate node low when the logic circuit is in an initial state with the MOS input transistor turned off.
    Type: Grant
    Filed: March 15, 1991
    Date of Patent: June 16, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Dennis L. Wendell
  • Patent number: 5122920
    Abstract: An integrated circuit is shown in which provision is made for terminating or locking out the operating circuitry when the supply voltage has fallen below a level that can cause anomalous or unreliable operation. Certain selected transistors are provided with saturation sensors which operate to produce a current when the transistors go into collector saturation. When any of the sensors indicates the onset of saturation, clamping circuitry is energized to provide lock out. In addition, a temperature compensated dummy bandgap circuit is included to sense extremely low supply voltages and provide the lockout function under conditions where a reliable saturation indication might not be available.
    Type: Grant
    Filed: August 22, 1988
    Date of Patent: June 16, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Robert A. Pease
  • Patent number: 5117276
    Abstract: A semiconductor integrated circuit device includes a high performance interconnect structure which comprises a plurality of interconnects, with each interconnect being structurally separated from the remaining interconnects except at electrical contact points. In one embodiment, each interconnect is substantially surrounded by a layer of dielectric material, there being gaps between each adjacent layer of surrounding dielectric material. Another embodiment, a layer of electrically conductive material is formed over the surrounding dielectric layer preferably filling in the gaps between adjacent layers of surrounding dielectric material. The layer of electrically conductive material acts as a ground plane and heat sink.
    Type: Grant
    Filed: November 8, 1990
    Date of Patent: May 26, 1992
    Assignee: Fairchild Camera and Instrument Corp.
    Inventors: Michael E. Thomas, Jeffrey D. Chinn
  • Patent number: 5117125
    Abstract: A logic level control circuit prevents impact ionization in a CMOS integrated circuit. The substrate bias voltage of the CMOS integrated circuit is detected by the control circuit and a control signal is provided in response to the detected bias voltage. The bias voltage can be zero volts or negative five volts. If the bias voltage is zero volts, the control signal is a logic level one. If the bias voltage is negative five volts, the control signal is a logic level zero. The control signal is applied to the gate of at least one other controlled device on the integrated circuit for turning the controlled device on and off. The controlled device coupled to a further CMOS device and turning the controlled device on and off prevents impact ionization by allowing the controlled device to alternately divide a voltage level with the further CMOS device or be effectively removed from the circuit.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: May 26, 1992
    Assignee: National Semiconductor Corp.
    Inventor: Michael K. Mayes
  • Patent number: 5111355
    Abstract: A thin film capacitor for use in an integrated circuit includes a lower plate disposed on the silicon substrate of the integrated circuit. The lower plate comprises a barrier layer of conductive material which prevents transport of silicon from the silicon substrate into a layer of dielectric material which is disposed between the lower plate and an upper plate. A portion of the barrier layer can be consumed and transferred into dielectric material by, for example, high temperature oxidation which generates a symmetric series capacitor with the dielectric layer. A layer comprising an oxide of the barrier layer material is formed between the barrier layer and the dielectric layer by consuming an upper portion of the barrier layer.
    Type: Grant
    Filed: September 13, 1990
    Date of Patent: May 5, 1992
    Assignee: National Semiconductor Corp.
    Inventors: Kranti V. Anand, Michael E. Thomas
  • Patent number: 5111276
    Abstract: There is disclosed a structure for self aligned and non-self aligned power and ground buses and interconnects for integrated circuits which are thicker than normal conductors. This enables them to withstand higher current densities without adverse electromigration effects. There is also disclosed a method for making such structures.
    Type: Grant
    Filed: November 19, 1990
    Date of Patent: May 5, 1992
    Assignee: National Semiconductor Corp.
    Inventors: Hemraj Hingarh, Andres D. Asuncion, Michael Thomas, Robert Brown
  • Patent number: 5107189
    Abstract: An RGB video display terminal (VDT) is disclosed and the color cathode ray tube (CRT) driver circuits detailed. The driver circuits include a common video gain control which can be varied over a wide range without changing the DC bias level. Each CRT gun can have its driver gain separately controlled over a vernier range and its DC bias can be separately controlled. The video amplifier is AC coupled to the video input and includes a DC reinsertion circuit which clamps the DC bias at a level related to the composite video level immediately following the sync pulse. Therefore, the DC reinsertion is clamped for each scanning line at the CRT black level. The video amplifier also includes a blanking circuit which turns the CRT guns off during the VDT retrace interval. Thus, the driver circuits can drive the CRT guns in a manner that will simultaneously control their operation for the color display and yet take into account the manufacturing tolerance in individual gun characteristics.
    Type: Grant
    Filed: February 15, 1991
    Date of Patent: April 21, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Ronald W. Page
  • Patent number: 5094972
    Abstract: An integrated circuit device is fabricated upon a semiconductor wafer by first forming a stop layer upon the surface of the wafer. Holes are formed through the stop layer and wells are formed in the semiconductor material of the semiconductor wafer below the openings. A dielectric layer is formed over the the surface of the device substantially filling the wells and covering the stop layer. The dielectric layer is then planarized to substantially the level of the stop layer. A PAD oxide layer is provided between the stop layer and the surface of the semiconductor device. Conventional thin film oxidation of the wells and implants into the side walls of the wells are performed. An abrasive mechanical polisher is used to perform the planarization wherein the mechanical polisher is provided with the self-stopping feature when it encounters the stop layer.
    Type: Grant
    Filed: June 14, 1990
    Date of Patent: March 10, 1992
    Assignee: National Semiconductor Corp.
    Inventors: John M. Pierce, Sung T. Ahn
  • Patent number: 5091048
    Abstract: The surface of a semiconductor wafer is planarized by disposing the wafer in a wafer plane and rotating the wafer within the wafer plane wherein the rotation is around an axis perpendicular to the plane. A stream of particles is transported to the surface of the wafer while the wafer is rotating wherein the angle between the stream of particles and the wafer plane is small. The stream of particles mills the surface of the wafer thereby planarizing the surface of the wafer. The angle between the stream of particles and the wafer plane is preferably less than thirty degrees. The particles may be argon ions and may be chemically active particles or physical particles.
    Type: Grant
    Filed: September 17, 1990
    Date of Patent: February 25, 1992
    Assignee: National Semiconductor Corp.
    Inventor: Michael E. Thomas
  • Patent number: 5089728
    Abstract: A CMOS switch driver capable of driving a plurality of CMOS switches is disclosed. A pair of cascade coupled output inverters provide the complementary driver outputs. Their inputs are obtained respectively from the first of the pair and a third, or input, inverter. The circuit includes resistance elements in the output inverters that greatly reduce current spikes.
    Type: Grant
    Filed: September 6, 1989
    Date of Patent: February 18, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Thai M. Nguyen
  • Patent number: 5084633
    Abstract: A circuit capable of being integrated into a self-isolated DMOST is driven by a sense resistor that is created from the DMOST drain metallization. The circuit produces an output current that is ratioed with respect to the DMOST current with the ratio being determined by the value of a single resistor. The output current is sourced when the DMOST conducts its source current and the output current is sunk when the DMOST shunt diode conducts. Thus, the circuit not only produces a DMOST current related output it also distinguishes the mode of DMOST conduction.
    Type: Grant
    Filed: October 19, 1990
    Date of Patent: January 28, 1992
    Assignee: National Semiconductor Corporation
    Inventor: Mansour Izadinia
  • Patent number: 4123091
    Abstract: A flow-through or fluid coupling connector assembly possessing positive locking connect and ready disconnect comprising two connector bodies; one having a male tubular member, and the other having a female tubular member for receiving the male member upon connection of the two bodies together. The male tubular member of the one connector body has resilient arm members spaced from and extending along opposite sides of the tubular member's axis with the free remote ends of the arms flaring outwardly therefrom. The arm members are each provided with an inwardly projecting flange member for locking the two connector bodies together by fitting into a recessed collar on the other connector body.
    Type: Grant
    Filed: November 21, 1977
    Date of Patent: October 31, 1978
    Assignee: Renal Systems, Inc.
    Inventors: Louis C. Cosentino, B. Steven Springrose
  • Patent number: 4121070
    Abstract: An enclosed push button switch in which movable and fixed contact members are mounted on the switch frame, the assembly being enclosed by a protective covering which is deformable on the upper surface thereof and in contact with the movable contact member of the switch to permit operation of the same through the cover.
    Type: Grant
    Filed: March 4, 1977
    Date of Patent: October 17, 1978
    Assignee: Renal Systems, Inc.
    Inventor: John P. Silbernagel
  • Patent number: 4010760
    Abstract: A body implantable electromedical device such as a cardiac pacemaker in which the stimulating signal generator module is detachably coupled to at least one of the power source modules and the leads, coupling being provided by assemblies which are body fluid corrosion resistant and inhibit current leakage between units of the assembly at different electrical potentials.
    Type: Grant
    Filed: May 23, 1975
    Date of Patent: March 8, 1977
    Assignee: Medtronic, Inc.
    Inventors: Robert E. Kraska, Pieter M. J. Mulier
  • Patent number: 3999555
    Abstract: A body implantable lead and insertion tool for attaching the lead to an internal body organ. The lead carries an electrode having first and second spaced organ engaging pincers. The insertion tool comprises jaws for firmly grasping the first and second spaced organ engaging pincers for facilitating the attachment thereof to a fold of the internal organ between the pincers. The pincers may be mechanically deformed to a closed position through opposing sides of the body organ fold by the application of a mechanical deforming force to and through the insertion tool. The tool also has a stop member for limiting the deformation of the first and second spaced organ engaging pincers to a predetermined extent.
    Type: Grant
    Filed: October 28, 1975
    Date of Patent: December 28, 1976
    Assignee: Medtronic, Inc.
    Inventor: Gerald C. Person