Norman C Walker

US Patent:

6661267, Dec 9, 2003

Filed:

May 6, 2002

Appl. No.:

10/139931

Inventors:

Norman Hugo Walker - San Diego CA
Victor Moy - Poughkeepsie NY
Michael A. Sorna - Hopewell Junction NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

H03L 706

US Classification:

327159, 331 44

Abstract:

A calibration system for a Phase Locked Loop (PLL) includes a phase/frequency detector coupled to the output of a voltage controlled oscillator (VCO) and to a source of a reference frequency. A charge pump is connected to receive an error signal from the phase/frequency detector and provide a voltage to a low pass filter. The low pass filter provides a filtered error signal to the VCO and to a comparator system. The comparator system provides a comparator output signal indicating when the polarity of the error signal exceeds a positive limit or a negative limit. A calibration means continuously provides incremental calibration inputs to the VCO, after a time delay. Thus the frequency of the VCO in the PLL is continuously corrected to compensate for frequency drift, and avoid jitter caused by an excessive rate of response to calibration inputs.

US Patent:

49823507, Jan 1, 1991

Filed:

Jun 10, 1987

Appl. No.:

7/060727

Inventors:

Nicholas A. Perna - Eltoro CA
Norman C. Walker - Solana Beach CA

Assignee:

Odetics, Inc. - Anaheim CA

International Classification:

G04F 1000

US Classification:

364569

Abstract:

An integrated system for precise measurement of time intervals wherein a high resolution and accuracy can be achieved through the implementation of an interpolation function and a self calibration function. The interpolation function scales down a relatively coarse major time base to a finer time base for the portions near the boundaries of the time interval that is being measured. The calibration function is built into the system for facilitating calibration of the interpolation function under actual operating of the system.

US Patent:

20180024169, Jan 25, 2018

Filed:

Jul 20, 2016

Appl. No.:

15/215358

Inventors:

- Orange CA, US
Norman C. Walker - Solana Beach CA, US

International Classification:

G01R 15/18
H01F 27/28

Abstract:

A small wire is wound several times around a powdered metal toroidal core to sense voltage produce by single polarity current flowing through a larger wire passing through the toroid. An integrator circuit integrates the voltage in the small wire to produce an output voltage as a measure of AC and DC components of the single polarity current, such as a full wave rectified current.