Patents by Inventor Donald E. Strayer

Donald E. Strayer 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).

  • Diffrential charge pump with integrated common mode control
    Patent number: 5619161
    Abstract: A phase locked loop circuit includes a phase/frequency detector which uses a divider circuit and feedback from a clock distribution tree to generate INC and DEC pulses which have no "dead zone". A pair of charge pumps receives the INC and DEC pulses. One charge pump is a differential pump and has voltage controlled common mode feedback circuit to maintain a common mode controlled voltage. A differential current is outputted to a loop filter capacitor by this charge pump. The other charge pump is a single-ended output pump which supplies current to a current controlled oscillator which also receives input from a voltage to current converter. The current controlled oscillator includes a variable resistance load which varies inversely with the magnitude of the input current. A jitter control circuit is provided which reduces jitter in the current controlled oscillator output in the locked phase.
    Type: Grant
    Filed: March 5, 1996
    Date of Patent: April 8, 1997
    Assignee: International Business Machines Corporation
    Inventors: Ilya l. Novof, Donald E. Strayer
  • Phase locked loop circuit with phase/frequency detector which eliminates dead zones
    Patent number: 5546052
    Abstract: A phase locked loop circuit is provided which includes a phase/frequency detector which uses a divider circuit and feedback from a clock distribution tree to generate INC and DEC pulses which do not have "dead zones". A pair of charge pumps receives the INC and DEC pulses. One charge pump is a differential pump and has a voltage controlled common mode feedback circuit to maintain a common mode controlled voltage. A differential current is outputted to a loop filter capacitor by this charge pump. The other charge pump is a single-ended output pump which supplies current to a current controlled oscillator which also receives input from a voltage to current converter. The current controlled oscillator includes a variable resistance load which varies inversely with the magnitude of the input current. A jitter control circuit is also provided which reduces jitter in the current controlled oscillator output in the locked phase.
    Type: Grant
    Filed: November 10, 1994
    Date of Patent: August 13, 1996
    Assignee: International Business Machines Corporation
    Inventors: John S. Austin, Ilya I. Novof, Donald E. Strayer, Stephen D. Wyatt
  • Resistorless phase locked loop circuit employing direct current injection
    Patent number: 5513225
    Abstract: A phase locked loop circuit includes a phase/frequency detector which uses a divider circuit and feedback from a clock distribution tree to generate INC and DEC pulses which have no "dead zone". A pair of charge pumps receives the INC and DEC pulses. One charge pump is a differential pump and has voltage controlled common mode feedback circuit to maintain a common mode controlled voltage. A differential current is outputted to a loop filter capacitor by this charge pump. The other charge pump is a single-ended output pump which supplies current to a current controlled oscillator which also receives input from a voltage to current converter. The current controlled oscillator includes a variable resistance load which varies inversely with the magnitude of the input current. A jitter control circuit is provided which reduces jitter in the current controlled oscillator output in the locked phase.
    Type: Grant
    Filed: August 31, 1994
    Date of Patent: April 30, 1996
    Assignee: International Business Machines Corporation
    Inventors: Ram Kelkar, Ilya I. Novof, Donald E. Strayer, Stephen D. Wyatt