Robert W Dotson

US Patent:

6759891, Jul 6, 2004

Filed:

Apr 29, 2002

Appl. No.:

10/133761

Inventors:

Robert N. Dotson - Chandler AZ

Assignee:

Semiconductor Components Industries, L.L.C. - Phoenix AZ

International Classification:

G05F 326

US Classification:

327512, 327361, 327540, 361103, 323315

Abstract:

An integrated circuit ( ) includes a thermal shutdown circuit that incorporates hysteresis for shutting down a functional circuit ( ) when its temperature exceeds a predefined value. First and second current sources ( ) respectively produce first and second reference currents (I , I ) representative of first and second die temperatures of the integrated circuit. A current mirror ( ) has an input ( ) for summing the first and second reference currents and an output ( ) for providing a mirror current (I ). A detection circuit ( ) has an output coupled to the output of the current mirror for sinking the mirror current to produce a detection signal (V ) as a function of the first and second die temperatures.

US Patent:

57342962, Mar 31, 1998

Filed:

Mar 19, 1996

Appl. No.:

8/618671

Inventors:

Robert N. Dotson - Chandler AZ
Richard S. Griffith - Chandler AZ
Robert L. Vyne - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03F 345
H03F 316

US Classification:

330253

Abstract:

Low voltage operational amplifier (10) operates in a voltage range of one to eight volts over a temperature range of 0. degree. to 70. degree. centigrade. Op amp input stage (12) uses N-channel depletion-mode MOSFETs to provide amplification of the differential input and maintain constant transconductance. Source follower MOSFET (13) provides unity gain in transferring the AC signal, STAGE-1 OUTPUT, to the base of current sinking transistor (18). Sink control circuit (14) and source control circuit (22) generate the base drive currents for transistors (18) and (24). The signal at the output of MOSFET (13) either causes the sink transistor (18) to sink current or the signal to be transposed by means of a translinear loop (16) and causes the source transistor (24) to source current. An output stage provides approximately fifty milliamps of current drive and is quiescent until the output driver is selected.

US Patent:

56990154, Dec 16, 1997

Filed:

Mar 19, 1996

Appl. No.:

8/618544

Inventors:

Robert N. Dotson - Chandler AZ
Richard S. Griffith - Chandler AZ
Thomas D. Petty - Tempe AZ
Robert L. Vyne - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03F 345
H03F 326
H03F 316

US Classification:

330255

Abstract:

Low voltage operational amplifier (10) operates in a voltage range of one to eight volts over a temperature range of 0. degree. to 70. degree. centigrade. Op amp input stage (12) uses N-channel depletion-mode MOSFETs to provide amplification of the differential input and maintain constant transconductance. Source follower MOSFET (13) provides unity gain in transferring the AC signal, STAGE-1 OUTPUT, to the base of current sinking transistor (18). Sink control circuit (14) and source control circuit (22) generate the base drive currents for transistors (18) and (24). The signal at the output of MOSFET (13) either causes the sink transistor (18) to sink current or the signal to be transposed by means of a translinear loop (16) and causes the source transistor (24) to source current.