Michael J Delurio

US Patent:

6376934, Apr 23, 2002

Filed:

Aug 18, 1999

Appl. No.:

09/376236

Inventors:

Michael J. DeLurio - Campbell CA

Assignee:

Sipex Corporation - Billerica MA

International Classification:

H05B 3700

US Classification:

307125, 3151693, 315209 R

Abstract:

A method and circuit for generating a voltage waveform across a capacitive load such as an electroluminescent device is described. The method includes the steps of charging and discharging the capacitive load using a constant current source. By sequentially performing the steps of providing a constant current through the capacitive load, eliminating the current, and discharging the capacitive load, a trapezoidal voltage waveform is achieved. In portable telephones and laptop computers with electroluminescent displays, the trapezoidal waveform results in reduced audible noise and power consumption.

US Patent:

20090128110, May 21, 2009

Filed:

Nov 16, 2007

Appl. No.:

11/941341

Inventors:

Michael DeLurio - Campbell CA, US
Charles Vinn - Milpitas CA, US

Assignee:

MICREL, INC. - San Jose CA

International Classification:

G05F 1/00

US Classification:

323282

Abstract:

A compensation circuit in a monolithic switching regulator controller being incorporated in a closed loop feedback system of a switching regulator includes error amplifier having an output terminal with an output impedance and a degeneration resistance terminal coupled to a first terminal of the switching regulator controller. The compensation circuit includes a first resistor and a first capacitor connected in series between the output terminal of the error amplifier and a ground potential. In operation, the first capacitor and the output impedance of the error amplifier operate to introduce a pole and the first resistor and the first capacitor operate to introduce a first zero in the closed loop feedback system. When a second capacitor is coupled to the first terminal of the switching regulator controller, a second zero is introduced in the closed loop feedback system. The second capacitor is an off-chip capacitor formed external to the monolithic switching regulator controller.

US Patent:

51793610, Jan 12, 1993

Filed:

May 15, 1991

Appl. No.:

7/700279

Inventors:

Nasrollah S. Navid - Saratoga CA
Michael J. DeLurio - San Jose CA

Assignee:

North American Philips Corp. - Tarrytown NY

International Classification:

H04B 164

US Classification:

333 14

Abstract:

A compandor system is provided that uses integrated circuitry in combination with fully external controlling devices for unity gain level adjustment without affecting the dynamic range. In addition, the system's stability is maintained. The external control is provided, for instance, by replaceable discrete resistors.