Patents Assigned to VLSI Technologies, Inc.
  • Patent number: 6091272
    Abstract: The present invention is directed to a method and apparatus for producing a square wave output signal with a clock circuit that possesses characteristics of low current consumption, relatively tight duty cycle control, and versatility over a wide range of voltages and input signal frequencies down to, and including DC. Exemplary embodiments receive an input signal, and process the input signal into an output square wave signal. A processing of the input signal is achieved using at least one current mirror for controlling a duty cycle of the output square wave signal said at least one current mirror being implemented in part with at least one pair of cascoded transistors. The processing is further achieved with an output stage having at least one inverter operatively connected with a node between the transistors of the at least one pair of cascoded transistors to control switching of the at least one pair of cascoded transistors.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: July 18, 2000
    Assignee: VLSI Technologies, Inc.
    Inventor: Clive Roland Taylor
  • Patent number: 6062480
    Abstract: A hot docking system and method for managing and detecting hot docking of bus cards. The hot docking system detects the load impedance at the power pins of the bus connector to determine whether a card has been inserted. When insertion is detected, bus activity on the connector is ceased until the card is completely inserted which is indicated by signals present on card detect pins which are mechanically shorter that the bus signal pins and thereby provide this insertion signal after all other connections are complete. The power supply pins are mechanically longer than the bus signal pins thereby providing an early indication that a card has been inserted. On removal of the card, the card detect pins disconnect before the bus signal pins or the power supply pins, signaling the system to halt bus activity but maintain power on the connector until the card is completely removed.
    Type: Grant
    Filed: July 20, 1998
    Date of Patent: May 16, 2000
    Assignee: VLSI Technologies, Inc.
    Inventor: David Ross Evoy
  • Patent number: 5990561
    Abstract: A method for producing a glue layer for an integrated circuit which uses tungsten plugs in accordance with the present invention includes: (A) providing a substrate which has a surface, a center, an edge, and a direction normal to the surface; and (B) sputter depositing a glue layer over the surface of the substrate such that an edge thickness of the glue layer measured in the direction normal to the surface at the edge of the substrate is at least 105% of a center thickness of the glue layer measured in the direction normal to the surface at the center of the substrate.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: November 23, 1999
    Assignee: VLSI Technologies, Inc.
    Inventors: Calvin T. Gabriel, Dipankar Pramanik, Xi-Wei Lin
  • Patent number: 5471153
    Abstract: The present invention is directed to methods and circuits for testing open collector or open drain output pads. In a preferred embodiment, the open collector or open drain outputs are hard driven to both their normal low and high level logic states during a test mode of operation. By actively driving open collector or open drain output pads to both their active and their inactive states, the existence of a stable output at any given sample time is guaranteed during a functionality test. The need to accurately estimate time delays associated with RC loads of external circuitry and the need to precisely strobe an open collector or open drain output following transition to an inactive, disabled state are therefore eliminated. Further, control signal inputs associated with a high impedance condition of open collector or open drain output pads can be directly examined at the circuit output using appropriate test logic.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: November 28, 1995
    Assignee: VLSI Technologies, Inc.
    Inventor: William C. Martin