Thomas A Schmidt

US Patent:

6717530, Apr 6, 2004

Filed:

Aug 14, 2000

Appl. No.:

09/638839

Inventors:

Thomas A. Schmidt - Dallas TX
Andrew Marshall - Dallas TX
Jingwei Xu - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G08B 2926

US Classification:

34087017, 34087016, 702130, 702132

Abstract:

A temperature sensing system ( ) that providing at least one detect signal related to temperature in an integrated circuit is presented. This system uses one thermal sensing circuit ( ) to detect two or more temperature thresholds (t , t ) and differentiates the temperature thresholds using time multiplexed logic control. The system ( ) capable of detecting more than two temperatures includes the thermal sensing circuit ( ) and a decode circuit ( ) with at least one detect latch ( ). Optionally, the system may include a hysteresis circuit ( ). The thermal sensing circuit ( ), connected to the integrated circuit, generates a detect signal (D ) in response to the a temperature selection signal (T ). This flexible on-board temperature monitoring solution reduces the cost of thermal feedback sensing by reducing die area and improves the correlation of detected temperatures. In addition, this solution reduces the possibility of mismatch and tracking errors between two or more sense elements.

US Patent:

7035071, Apr 25, 2006

Filed:

Dec 29, 2004

Appl. No.:

11/025706

Inventors:

Kee Chee Tiew - Richardson TX, US
Thomas A. Schmidt - Murphy TX, US
Brett E. Smith - McKinney TX, US
John C. Vogt - Denton TX, US
Abidur Rahman - Allen TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02H 9/08

US Classification:

361 939, 700 33

Abstract:

A switching regulator having a current limit with adaptive cycle skipping. A buck type switching regulator circuit is provided, including an energy storage component, such as an inductor or capacitor, and a switch for controllably providing an input current to the energy storage component. A control unit controls the on time and the off time of the switch by providing cyclically recurring control pulses to the switch that cause the switch to be on during the pulses and off otherwise. A current monitor circuit monitors a current corresponding to the input current applied to the energy storage component during the periodic control pulses. An overcurrent signal generator generates an overcurrent signal pulse upon detection of the monitored current at a level above a predetermined level corresponding to an overcurrent condition. A state machine responds to the overcurrent signal pulse and suppresses a number of the cyclically recurring control pulses, thereby controlling the period between the recurring control pulses that are not suppressed, in accordance with a predetermined algorithm that increases the number each time an overcurrent signal pulse is detected in successive periods.

US Patent:

7071740, Jul 4, 2006

Filed:

Sep 28, 2004

Appl. No.:

10/951969

Inventors:

Reed W. Adams - Plano TX, US
Thomas A. Schmidt - Murphy TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H03B 1/00

US Classification:

327110, 327389, 327427

Abstract:

A FET switching transistor for the solenoid coil of an ABS braking system can switched ON or OFF in no more than substantially 250 ns. A higher current biasing circuit for fast turn on of the FET switching transistor is disconnected when it is necessary to limit the current flowing therethrough, whether during the inrush current to the solenoid coil or due to a fault in the system. The high speed switching of the FET switching transistor causes ringing of the current through the transistor which causes the current detector circuit to exit the current control mode. A deglitch circuit prevents the current detector from exiting the current control mode, so that a timer can be used to turn off the FET switching transistor before it can be damaged by the heat generated during current limit operation.

US Patent:

7236003, Jun 26, 2007

Filed:

Sep 29, 2005

Appl. No.:

11/239021

Inventors:

Shanmuganand Chellamuthu - Richardson TX, US
Brett E. Smith - McKinney TX, US
Thomas A. Schmidt - Murphy TX, US
Abidur Rahman - Allen TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H03K 19/007

US Classification:

326 14, 326 27, 363 50

Abstract:

The H-bridge circuit with shoot through current prevention during power-up includes: a high side transistor; a low side transistor coupled in series with the high side transistor; pull down devices coupled to a control node of the high side transistor and to a control node of the low side transistor; and wherein the pull down devices are controlled by a pull down circuit including a Power On Reset circuit, monitoring the digital power supply such that the high side and low side transistors are OFF until the digital power supply has settled to a desired operating voltage.

US Patent:

7817393, Oct 19, 2010

Filed:

Aug 26, 2008

Appl. No.:

12/198360

Inventors:

Thomas A. Schmidt - Murphy TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02H 3/08
H02H 9/02

US Classification:

361 932, 361 937, 361 931

Abstract:

Methods and apparatus to provide power distribution switch circuits with fast responses to hard short-circuits are disclosed. In one example, a power distribution switch to detect a hard short-circuit condition is described, comprising a switching device having a resistance between an input terminal and an output terminal, to conduct a current from an input power source having an input voltage to an output terminal having an output voltage, a voltage feedback loop having a digital output voltage to increase the resistance of the switching device in response to a short-circuit based on the output voltage, and an analog current feedback loop to increase the resistance of the switching device based on a current through the switching device and a reference current.

US Patent:

8040652, Oct 18, 2011

Filed:

Aug 26, 2008

Appl. No.:

12/198353

Inventors:

Thomas A. Schmidt - Murphy TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02H 9/06
H02H 3/08
H02H 9/02

US Classification:

361 939, 361 931

Abstract:

Programmable power distribution switches with two-level current sensing are disclosed. In a particular example, a power distribution switch includes a programmable output device having a resistance based on a programmed maximum output current and generates an output voltage based on the resistance and a load current. The example power distribution switch also includes a reference voltage generator that is configured to generate a reference voltage corresponding to the output voltage when the load current is substantially equal to the programmed maximum output current. A current limiter is also included to reduce the load current in response to a comparison of the output voltage and the reference voltage, when the comparison is indicative of the load current exceeding the programmed maximum output current.

US Patent:

20110193539, Aug 11, 2011

Filed:

Feb 10, 2010

Appl. No.:

12/703725

Inventors:

Thomas A. Schmidt - Murphy TX, US
Robert Martinez - Lucas TX, US
Wenliang Chen - Plano TX, US
Wei-Chung Wu - Richardson TX, US

Assignee:

TEXAS INSTRUMENTS INCORPORATED - Dallas TX

International Classification:

G05F 1/10

US Classification:

323282

Abstract:

A switching regulator generally includes an output circuit, a comparator, an on-time timer and an error amplifier. The output circuit receives an input voltage and produces an output voltage. The comparator causes the output circuit to turn on the output voltage when a feedback voltage falls below a first reference voltage. The on-time timer causes the output circuit to turn off the output voltage after a time-out period. The error amplifier receives the feedback voltage and a second reference voltage and produces the first reference voltage.

US Patent:

55281257, Jun 18, 1996

Filed:

Apr 5, 1995

Appl. No.:

8/416663

Inventors:

Andrew Marshall - Dallas TX
Thomas A. Schmidt - Dallas TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G05F 110
G05F 140

US Classification:

323222

Abstract:

A buck-boost switch mode regulated power supply using a burst circuit topology includes a detection circuit to sense overcurrent in the high side connected power transistor. This causes the flip flop to flip which turns off the transistor. A comparator connected to the output voltage detects when the output voltage falls below the threshold value of the comparator and sends a signal to the flip flop which is reset upon the next pulse of a pulsed reset signal. When the flip flop is reset, the high side power transistor is turned back on.