JAMES ALLAN WILLIAMS
Pilots at Alma St, Palo Alto, CA

5767630, Jun 16, 1998

Sep 18, 1996

8/715428

James M. Williams - Palo Alto CA

Linear Technology Corporation - Milpitas CA

H05B 4116

315282

Power supply and control circuits are provided for driving a fluorescent lamp with a differential drive voltage from a low voltage DC power source. In one embodiment, the lamp is driven by a transformer having a primary and two independent secondary windings which produce the differential drive signal. A feedback signal indicative of the magnitude of current conducted by the lamp is produced from one of the secondary windings that is coupled to the control circuit so that the feedback signal is directly proportional to the energy required to light the lamp. In another embodiment, the lamp is driven by two independent transformers that are both driven by the control and drive circuit. The two secondary windings are each connected to one end of the lamp so that the lamp is driven by a differential drive signal. One of the secondary windings is also coupled to the control and drive circuit to provide a feedback signal indicative of the magnitude of current conducted by the lamp.

5408162, Apr 18, 1995

Mar 31, 1993

8/043152

James M. Williams - Palo Alto CA

Linear Technology Corporation - Milpitas CA

H05B 4136

315224

A power supply and control circuit is provided for driving a fluorescent lamp from a low voltage DC power source such as a battery. A DC-to-AC inverter coupled to a switching regulator converts low DC voltage into a higher AC voltage for driving the fluorescent lamp. The lamp is included in a feedback loop which includes a circuit for producing a feedback signal indicative of the magnitude of current conducted by the lamp. The feedback signal is applied to the switching regulator to produce in the lamp a regulated current and, hence, a regulated lamp intensity. The magnitude of the lamp current can be adjusted to enable the intensity of the fluorescent lamp to be smoothly and continuously varied (without "dead-spots" or "pop-on") over a chosen intensity range, including if desired, from substantially full OFF to full ON. A method for driving a fluorescent lamp from a low voltage DC power source is also provided.

7021833, Apr 4, 2006

Mar 22, 2002

10/104249

James Chang - Cupertino CA, US
Pradeep Raj Komar - San Jose CA, US
Brenton A. Baugh - Palo Alto CA, US
Ronald T. Kaneshiro - Los Altos CA, US
Robert E. Wilson - Palo Alto CA, US
James Williams - Palo Alto CA, US

G02B 6/36

385 88, 385 92, 385 94

Waveguide based connector systems for optically coupling a fiber optic cable and an optoelectronic device and a method of fabricating the same are described. In one aspect, a connector system comprises an optical waveguide and an optical turn assembly. The optical waveguide has a first end and a second end. The first end of the optical waveguide is connectable to the fiber optic cable in an orientation aligned with a line-side connection axis. The optical turn assembly has a first optical port that is connected to the second end of the optical waveguide in an orientation aligned with a device-side connection axis, a second optical port that is oriented to communicate optically with the optoelectronic device along a device communication axis substantially intersecting the device-side connection axis, and an optical turn system that is operable to guide light along a path between the first optical port and the second optical port.

5548189, Aug 20, 1996

Jun 7, 1995

8/483374

James M. Williams - Palo Alto CA

Linear Technology Corp. - Milpitas CA

H05B 3702

315224

A power-supply and control circuit is provided for driving a fluorescent lamp from a low-voltage DC power source such as a battery. In typical lamp-driving circuits, a step-up transformer is used to apply well known magnetic techniques to achieve the low-to-high voltage conversion required by the lamp. The present invention uses a new approach, applying piezoelectric characteristics of certain ceramic materials to replace the magnetic transformer. Resonant characteristics of such ceramic materials permit them to be self-resonated. A DC-to-AC converter coupled to a switching regulator converts low DC voltage into a higher AC voltage for driving the fluorescent lamp. In one embodiment, the lamp is included in a feedback loop which includes a circuit for producing a feedback signal indicative of the magnitude of current conducted by the lamp. The feedback signal is applied to the switching regulator to produce in the lamp a regulated current and, hence, a regulated lamp intensity. A method for driving a fluorescent lamp from a low-voltage DC power source is also provided.

6127785, Oct 3, 2000

Nov 27, 1996

8/757995

James M. Williams - Palo Alto CA

Linear Technology Corporation - Milpitas CA

H05B 3702

315224

A power supply and control circuit is provided for driving a fluorescent lamp from a low voltage DC power source such as a battery. A DC-to-AC inverter coupled to a switching regulator converts low DC voltage into a higher AC voltage for driving the fluorescent lamp. In one embodiment, the lamp is included in a feedback loop which includes a circuit for producing a feedback signal indicative of the magnitude of current conducted by the lamp. In another embodiment, the lamp is symmetrically driven by isolating the lamp from the driving circuitry and indirectly deriving the feedback signal. The feedback signal is applied to the switching regulator to produce in the lamp a regulated current and, hence, a regulated lamp intensity. The magnitude of the lamp current can be adjusted to enable the intensity of the fluorescent lamp to be smoothly and continuously varied (without "dead-spots" or "pop-on") over a chosen intensity range, including if desired, from substantially full OFF to full ON. When the lamp is symmetrically driven, the lamp is illuminated in a more uniform manner long the entire length of the tube.

6087787, Jul 11, 2000

Nov 23, 1998

9/198193

James M. Williams - Palo Alto CA

Linear Technology Corporation - Milpitas CA

G05F 100

315307

A power-supply and control circuit is provided for driving a fluorescent lamp from a low-voltage direct current (DC) power source such as a battery. The circuit includes a converter that converts low-voltage DC to high voltage alternating current (AC). The converter includes a feedback ceramic step-up transformer that amplifies the AC signal to a level sufficient to illuminate the lamp, and also provides a feedback signal that can be used to monitor the resonance frequency of the transformer. The power supply and control circuit also includes a first feedback loop that regulates the lamp current amplitude and a second feedback loop that forces the converter to operate at the transformer's resonant frequency.

4554499, Nov 19, 1985

Oct 24, 1984

6/664110

Leonard H. Sherman - Sunnyvale CA
James R. Swartz - San Mateo CA
James M. Williams - Palo Alto CA

Genentech, Inc. - So. San Francisco CA

H02P 800

318696

To control a motor, a pulse width modulated signal from a computer is fed to a capacitor which stores each pulse as a voltage proportional to the width of the pulse, the capacitor being reset to zero by a leading edge reset circuit. The voltage on the capacitor is sampled by a sample/hold circuit the output of which is fed to a converter which converts the voltage signal to a frequency signal exponentially related to the voltage, and hence to the pulse width. The converter then powers a driver which drives the motor. The exponential relationship between the pulses and the signal fed to the motor permits a large variationin the frequency signal based on a small variation in pulse width and hence permits accurate control of the motor.

7622893, Nov 24, 2009

Mar 13, 2007

11/717126

James Michael Williams - Palo Alto CA, US

Linear Technology Corporation - Milpitas CA

H01M 10/46

320112

Various concepts and techniques are disclosed for measuring the voltage of a power source. An apparatus includes a voltage metering circuit and a transformer having a first winding coupled to the voltage metering circuit and a second winding for coupling to a power source.