Robert G 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:

44619898, Jul 24, 1984

Filed:

Aug 27, 1982

Appl. No.:

6/412069

Inventors:

Robert N. Dotson - Mesa AZ
Robert B. Davies - Tempe AZ
Ira Miller - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G05F 110
G05F 320

US Classification:

323222

Abstract:

In a voltage boost circuit for use in conjunction with a bubble memory operational driver, an output transistor alternately turns on and off so as to permit current to flow through an inductor which, when terminated by turning off the output transistor, causes a high voltage to be built up across the inductor which causes charge to be transferred to and stored in a capacitor. The output transistor is not turned on again until the voltage across the inductor falls below a predetermined value. A current mirror circuit is coupled to the comparator input and includes a buffer transistor which, when the voltage at the comparator input exceeds the break-down voltage of the buffer transistor, acts as a BV. sub. ceo level shifter.

US Patent:

45019797, Feb 26, 1985

Filed:

Aug 30, 1982

Appl. No.:

6/413054

Inventors:

Michael W. Null - Mesa AZ
Robert N. Dotson - Mesa AZ
Robert B. Davis - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03K 1762
H03F 304

US Classification:

307494

Abstract:

A current amplifier is provided having a single control amplifier and a plurality of output stages. The desired output stage is digitally selected. The ratios of the output stage currents may be selected during the metalization process. A single capacitor compensates for all output stages regardless of which output stage is selected.

US Patent:

57265976, Mar 10, 1998

Filed:

Aug 30, 1996

Appl. No.:

8/706095

Inventors:

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

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03K 522

US Classification:

327307

Abstract:

A trim circuit (10) and method of reducing offset voltages in a differential input stage. The differential input transistors (32 and 42) have separate bulk terminals for receiving a voltage to compensate for the input offset voltage. A current source (60) supplies a static current to the offset compensation circuit for generating a bias voltage at node (55). The transistors (64 and 66) receive a voltage at input terminals (30 and 40) and supply an additional current to an offset compensation circuit (20). A switch circuit (50) has switch pairs (52, 56, and 54, 58) for transferring a voltage to the bulk terminal of one of the differential transistors (32 and 42) while grounding the bulk terminal of the other transistor. The differential voltage supplied across the bulk terminals of transistors (32 and 42) changes the threshold voltage of the transistors reducing the offset voltage of the input stage.

US Patent:

45146489, Apr 30, 1985

Filed:

Aug 27, 1982

Appl. No.:

6/412057

Inventors:

Robert N. Dotson - Mesa AZ
Robert B. Davies - Tempe AZ
Ira Miller - Tempe AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03K 5153
H03K 524
H03K 1708

US Classification:

307350

Abstract:

In a voltage boost circuit for use in conjunction with a bubble memory operational driver, an output transistor is alternately turned on and off. When turned on, current flows through an inductor. When turned off, a high voltage is built up across the inductor which causes charge to be transferred to and stored in a capacitor. When the output transistor is turned on so as to permit current to flow through the inductor, a. DELTA. V. sub. BE /R current representative of the current flowing through the output transistor is compared with a. DELTA. V. sub. BE /R reference current. When the first current reaches and exceeds the reference current, the output transistor is turned off.

US Patent:

44853521, Nov 27, 1984

Filed:

Aug 30, 1982

Appl. No.:

6/413052

Inventors:

Robert B. Davies - Tempe AZ
Robert N. Dotson - Mesa AZ
Michael W. Null - Mesa AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03F 304

US Classification:

330288

Abstract:

A current amplifier uses a current mirror arrangement as an operational amplifier whose output has limited swing. The limited swing is achieved through a plurality of series connected diodes connected to a control input of the amplifier and to the output of the operational amplifier. The control input is coupled through a transistor to inhibit the output of the current mirror arrangement. The output node is coupled to an output for the current amplifier through a Darlington arrangement which provides high current gain.

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:

45544646, Nov 19, 1985

Filed:

Aug 30, 1982

Appl. No.:

6/413051

Inventors:

Robert B. Davies - Tempe AZ
Ira Miller - Tempe AZ
Robert N. Dotson - Mesa AZ

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H03K 3017
H03K 504
H03K 1756

US Classification:

307265

Abstract:

A propagation delay generator is provided for controlling the duration of a bubble generate waveform of a bubble memory system. A first means is responsive to a digital input signal and provides an initializing signal to a current source. A capacitor is charged, responsive to an R-C time constant, by an increased voltage level prompted by the initializing signal. A second means is responsive to the charging signal in excess of that required to charge the capacitor. The second means thereby provides a digital output that is delayed from the digital input signal.