Patents by Inventor Robert B. Craven

Robert B. Craven 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).

  • Solid state digital to analog converter
    Patent number: 4309693
    Abstract: An integrated-circuit 12-bit digital-to-analog converter comprising binarily-scaled constant-current sources with associated switch cells employing bipolar transistors to direct the bit currents either to a summing bus or to ground. The switch cells include a first differential transistor pair to translate a single-ended binary logic signal to double-ended (balanced) format, and a second, fully-balanced differential pair operated by the balanced logic signal to direct the bit current correspondingly. A bias-generating circuit maintains a constant collector-base voltage at the constant-current source. The threshold voltage for the logic signals can be set for TTL logic or, by pin-programming, for CMOS logic of either low-voltage or high-voltage type.
    Type: Grant
    Filed: September 4, 1979
    Date of Patent: January 5, 1982
    Assignee: Analog Devices, Incorporated
    Inventor: Robert B. Craven
  • Solid state digital to analog converter
    Patent number: 4141004
    Abstract: An integrated-circuit 12-bit digital-to-analog converter comprising binarily-scaled constant-current sources with associated switch cells employing bipolar transistors to direct the bit currents either to a summing bus or to ground. The switch cells include a first differential transistor pair to translate a single-ended binary logic signal to double-ended (balanced) format, and a second, fully-balanced differential pair operated by the balanced logic signal to direct the bit current correspondingly. A bias-generating circuit maintains a constant collector-base voltage at the constant-current source. The threshold voltage for the logic signals can be set for TTL logic or, by pin-programming, for CMOS logic of either low-voltage or high-voltage type.
    Type: Grant
    Filed: January 23, 1976
    Date of Patent: February 20, 1979
    Assignee: Analog Devices, Incorporated
    Inventor: Robert B. Craven
  • Solid state digital to analog converter
    Patent number: 3961326
    Abstract: An integrated-circuit 12-bit digital-to-analog converter comprising binarily-scaled constant-current sources with associated switch cells employing bipolar transistors to direct the bit currents either to a summing bus or to ground. The switch cells include a first differential transistor pair to translate a single-ended binary logic signal to double-ended (balanced) format, and a second, fully-balanced differential pair operated by the balanced logic signal to direct the bit current correspondingly. A bias-generating circuit maintains a constant collector-base voltage at the constant-current source. The threshold voltage for the logic signals can be set for TTL logic or, by pin-programming, for CMOS logic of either low-voltage or high-voltage type.
    Type: Grant
    Filed: September 12, 1974
    Date of Patent: June 1, 1976
    Assignee: Analog Devices, Inc.
    Inventor: Robert B. Craven