Gary S Engelson

US Patent:

49547887, Sep 4, 1990

Filed:

Dec 18, 1989

Appl. No.:

7/453356

Inventors:

Michael Leis - Framingham MA
Gary S. Engelson - Shrewsbury MA
Bruce J. Lawrence - Worcester MA

Assignee:

Digital Equipment Corporation - Maynard MA

International Classification:

H03L 700

US Classification:

331 16

Abstract:

A phase locked loop that operates on an input signal received from a disk drive and similar data processing system peripherals, where the input signal has a preamble portion and a data portion. The phase locked loop providing a digital clock signal which is phase locked to the preamble portion. This is accomplished by adjusting the loop response time so that it monotonically decreases in amplitude beginning at a time when the phase locked loop receives the preamble portion and continuing to monotonically decrease during at least a portion of the time that the phase locked loop receives the data portion. The response time may be monotonically decreased in any suitable fashion, such as linearly or exponentially. A specific embodiment of a linearly decreasing signal generator used with a charge pump is disclosed. The results of computer simulations showing a decrease in lock acquisition time and increased noise immunity with shortened preamble time are also discussed.

US Patent:

D4506871, Nov 20, 2001

Filed:

Sep 20, 2000

Appl. No.:

D/129719

Inventors:

James A. Batson - North Andover MA
Steve Hecker - Waltham MA
Mark Cooper - Somerville MA
Alan Ball - Somerville MA
Jonathan Marks - Cambridge MA
George Schnakenberg - Cambridge MA
Greg Flender - Bedford MA
Carl Betterley - Medford MA
Gary S. Engelson - Sharon MA

Assignee:

Pingtel Corp. - Woburn MA

International Classification:

1403

US Classification:

D14240

US Patent:

D4510917, Nov 27, 2001

Filed:

Sep 20, 2000

Appl. No.:

D/129721

Inventors:

James A. Batson - Andover MA
Steve Hecker - Waltham MA
Mark Cooper - Somerville MA
Alan Ball - Somerville MA
Jonathan Marks - Cambridge MA
George Schnakenberg - Cambridge MA
Daren Hebold - Boston MA
Greg Flender - Bedford MA
Carl Betterley - Medford MA
Gary S. Engelson - Sharon MA

Assignee:

Pingtel Corp. - Woburn MA

International Classification:

1403

US Classification:

D14240

US Patent:

D4385241, Mar 6, 2001

Filed:

Mar 20, 2000

Appl. No.:

D/120479

Inventors:

James A. Batson - North Andover MA
Steve Hecker - Waltham MA
Mark Cooper - Somerville MA
Alan Ball - Somerville MA
Jonathan Marks - Cambridge MA
George Schnakenberg - Cambridge MA
Daren Hebold - Boston MA
Greg Flender - Bedford MA
Carl Betterley - Medford MA
Gary S. Engelson - Sharon MA

Assignee:

Pingtel Corporation - Woburn MA

International Classification:

1403

US Classification:

D14151