Patents by Inventor James F. Testa

James F. Testa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5606270
    Abstract: A dynamic clocked inverter latch with reduced charge leakage includes a first node biasing circuit with a P-MOSFET and an N-MOSFET totem-pole-coupled between VDD and an output node, and a second node biasing circuit with another N-MOSFET and another P-MOSFET totem-pole-coupled between the output node and VSS. The first P-MOSFET receives an input data signal and the first N-MOSFET receives a clock signal and in accordance therewith together cause the output node to charge to a charged state having a charge voltage associated therewith. The second N-MOSFET also receives the input data signal while the second P-MOSFET receives the inverse of the clock signal and in accordance therewith together cause the output node to discharge to a discharged state having a discharge voltage associated therewith.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: February 25, 1997
    Assignee: Sun Microsystems, Inc.
    Inventors: Godfrey P. D'Souza, James F. Testa, Douglas A. Laird, James B. Burr
  • Patent number: 5583821
    Abstract: A storage cell includes a first bit line, a storage circuit, and a pass transistor. The storage circuit has a first storage node for holding a logic state indicative of a logic value. The pass transistor is coupled to the first bit line and the first storage node for establishing a conduction path therebetween. The pass transistor receives a bias voltage to switch the pass transistor into a substantially nonconducting state when the storage cell is not being accessed. The reverse bias on the first transistor substantially reduces the leakage current through the pass transistor.
    Type: Grant
    Filed: July 31, 1995
    Date of Patent: December 10, 1996
    Assignee: Sun Microsystems, Inc.
    Inventors: James W. Rose, Godfrey P. D'Souza, Jonathan J. Stinehelfer, James F. Testa
  • Patent number: 5568429
    Abstract: A data latch with reduced data signal leakage includes a latch circuit and a clock buffer circuit which provides a differential clock signal to the input transmission gate of the latch circuit. The clock buffer circuit is biased between upper and lower supply voltage potentials which are higher and lower, respectively, than those between which the latch circuit is biased. This causes the differential clock signal to be overdriven with respect to the incoming data signal which is latched by the latch circuit. As a result, the input transmission gate of the latch circuit is reverse-biased during the inactive state of the differential clock signal, thereby isolating the storage node within the latch circuit and preventing signal leakage therefrom.
    Type: Grant
    Filed: July 5, 1995
    Date of Patent: October 22, 1996
    Assignee: Sun Microsystems, Inc.
    Inventors: Godfrey P. D'Souza, James F. Testa
  • Patent number: 5488539
    Abstract: A method and apparatus is disclosed for protecting a solder pad for a chip on tape packaged integrated circuit mounted on a surface of a printed circuit board that is exposed to a wave soldering operation. A pad cover may be used to protect the solder pad. The pad cover is mounted over the solder pad in a manner that protects the solder pad from being exposed to solder during the wave solder operation. After the wave solder is completed, the cover is removed and the leads of the chip on tape packaged integrated circuit are connected to associated solder pad traces on the printed circuit board. This type of arrangement is particularly useful in arrangements which require a heat sink to cool the chip on tape packaged integrated circuit.
    Type: Grant
    Filed: January 21, 1994
    Date of Patent: January 30, 1996
    Assignee: Sun Microsystems, Inc.
    Inventors: James F. Testa, Jens Horstmann, Hassan Siahpolo
  • Patent number: 5471421
    Abstract: A storage cell includes a first bit line, a storage circuit, and a pass transistor. The storage circuit has a first storage node for holding a logic state indicative of a logic value. The pass transistor is coupled to the first bit line and the first storage node for establishing a conduction path therebetween. The pass transistor receives a bias voltage to switch the pass transistor into a substantially nonconducting state when the storage cell is not being accessed. The reverse bias on the first transistor substantially reduces the leakage current through the pass transistor.
    Type: Grant
    Filed: December 16, 1994
    Date of Patent: November 28, 1995
    Assignee: Sun Microsystems, Inc.
    Inventors: James W. Rose, Godfrey P. D'Souza, Jonathan J. Stinehelfer, James F. Testa