Randy T Heilman

US Patent:

6683896, Jan 27, 2004

Filed:

Mar 12, 2002

Appl. No.:

10/096739

Inventors:

Randy T. Heilman - Palm Bay FL
Taewon Jung - Malabar FL

Assignee:

Vitesse Semiconductor Corporation - Camarillo CA

International Classification:

H01S 300

US Classification:

372 2901, 372 38

Abstract:

A drive circuitry that drives a vertical cavity surface emitting laser is provided. The drive circuitry includes a modulator, a negative peak timer and a limiter. The negative peak timer causes the modulator to rapidly decrease the magnitude of the output signal of the modulator to dissipate charge stored on the laser. Thus, the vertical cavity surface emitting laser quickly turns off.

US Patent:

6933793, Aug 23, 2005

Filed:

Nov 24, 2003

Appl. No.:

10/721910

Inventors:

Randy T. Heilman - Melbourne FL, US

Assignee:

Vitesse Semiconductor Corporation - Camarillo CA

International Classification:

H03B005/30
H03B005/32
H03B005/36
H03B007/00

US Classification:

331 76, 331115, 331116 FE, 331132, 331154, 331158, 331183

Abstract:

A stable high-frequency clock pulse apparatus and method including frequency source, overtone crystal unit coupled with a negative resistance oscillator, a bandpass overtone filter and a drive level control is provided. The apparatus can include a frequency multiplier. The frequency source can be a micromechanical resonator.

US Patent:

50862421, Feb 4, 1992

Filed:

Oct 16, 1990

Appl. No.:

7/598165

Inventors:

Randy T. Heilman - Palm City FL
John S. Prentice - Palm Bay FL

Assignee:

Harris Corporation - Melbourne FL

International Classification:

H03K 1772
H01L 2974

US Classification:

307631

Abstract:

A fast turn-off thyristor including a first active shunt region in the cathode gate region connected electrically to the anode terminal for shunting carriers around the anode gate region in response to the thyristor being on and a second shunt region in the anode gate region connected electrically to the cathode terminal for shunting carriers around the cathode gate region in response to the thyristor being on. These active shunts are inactive until the thyristor is turned on and are structured to remain active until after the thyristor is turned off. The active shunts are transistors in parallel with the pair of interconnected transistors which are for a PNPN thyristor.

US Patent:

61671312, Dec 26, 2000

Filed:

Feb 20, 1998

Appl. No.:

9/027257

Inventors:

Randy Thomas Heilman - Palm Bay FL

Assignee:

Intersil Corporation - Melbourne FL

International Classification:

H04M 302

US Classification:

379373

Abstract:

In a local loop telephone system, a voltage limited device having circuitry to provide subscriber interface functions and generate a ring signal. The device comprises four switches in a full bridge drive configuration. An external source provides a constant voltage which converted into an alternating ring voltage by triggering the switches in a specified sequence.