David C Freeman

US Patent:

6369576, Apr 9, 2002

Filed:

Feb 3, 1997

Appl. No.:

08/794727

Inventors:

Wallace Edward Matthews - Richardson TX
David Louis Freeman - Plano TX
John Edward Landau - Mountain Lakes NJ

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01N 27416

US Classification:

324426, 320106, 320112, 320136

Abstract:

A battery charging system is provided which is comprised of a battery pack ( ) and a charging system ( ). The battery pack ( ) includes a battery ( ) and a battery capacity detect circuit ( ). The battery capacity detect circuit ( ) having a memory is interfaced with the charging system ( ) through a communication link to output a CHG-Bar signal. The battery capacity detect circuit ( ) is operable to perform numerous monitoring operations on the battery by detecting the charge input to the battery and detecting charge taken away from the battery in a discharge operation. This operation is performed independent of the charging operation by the charging system ( ). However, the charging operation of the charger ( ) can be affected with the CHG-Bar signal.

US Patent:

6377028, Apr 23, 2002

Filed:

Jul 29, 1996

Appl. No.:

08/681596

Inventors:

David Louis Freeman - Plano TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02J 700

US Classification:

320136

Abstract:

A battery monitoring/control device includes a monitor/control device ( ) that is operable to be integrated with a microprocessor system. The system includes a CPU ( ) that interfaces with a data bus ( ) and an address bus ( ). The CPU ( ) interfaces through a data line ( ) with the control/monitor device ( ) and control lines ( ) and ( ). Commands and data can be input to the control/monitor circuit ( ) and data received therefrom. The control/monitor device ( ) includes a controller/data register block ( ) and a battery charge control/monitor block ( ). The device ( ) is operable to monitor the battery voltage of a secondary battery ( ) during charging thereof and to control the rate of charge through a transistor ( ). The battery monitor ( ) determines when the voltage on the battery ( ) reaches a predetermined level indicating full-charge. A discharge circuit ( ) controls a discharge transistor ( ) to discharge the battery ( ) through a sense resistor ( ) for conditioning of the battery.

US Patent:

6577135, Jun 10, 2003

Filed:

Apr 9, 2002

Appl. No.:

10/119385

Inventors:

Wallace Edward Matthews - Richardson TX
David Louis Freeman - Plano TX
John Edward Landau - Mountain Lakes NJ

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G01N 27416

US Classification:

324426, 324427, 324428, 324429, 320106

Abstract:

A battery detect circuit ( ) is provided that is operable to dispose a sense resistor ( ) in series with the battery to determine whether the charge is being provided to the battery or being extracted from the battery. The voltage across the sensor resistor ( ) is sensed by a voltage/frequency converter ( ). The voltage/frequency converter ( ) is a differential structure comprised of two integrator structures ( ) and ( ) that are operable to utilize a switched capacitor configuration to drive comparators on the output thereof. Each of the integrator structures ( ) and ( ) has associated therewith passive elements and active elements. The integrators ( ) and ( ) have associated therewith integration capacitors ( ) and ( ). Additionally, there are two operational amplifiers ( ) and ( ) that provide the active components of each of the integrators ( ) and ( ). The various switched capacitor circuits ( ) and ( ) associated with the amplifiers ( ) and ( ) are provided to provide the integration operation.

US Patent:

6650089, Nov 18, 2003

Filed:

Oct 16, 2002

Appl. No.:

10/272110

Inventors:

David Freeman - McKinney TX
Jose Antonio Vieira Formenti - Allen TX

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02J 700

US Classification:

320132, 320130

Abstract:

A capacity gauge is provided that measures a selected battery capacity of a plurality of batteries in a multiple battery system. A capacity gauge and a battery current sense resistor reside on the end equipment, while the battery pack contains minimal information associated with the battery pack. Control circuits provide for proper pack selection and pack connection timing, as well as capacity gauge synchronization. Power up/down circuits provide power to control logic, the selection circuits and capacity gauge at power up, power down and battery pack removal. The system is powered by a selected battery pack after the battery pack selection is executed, and the selected battery pack monitored by the capacity gauge.

US Patent:

8570012, Oct 29, 2013

Filed:

Dec 13, 2011

Appl. No.:

13/324709

Inventors:

Tobin D. Hagan - Plano TX, US
Marco Corsi - Parker TX, US
David L. Freeman - McKinney TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

G05F 1/10
H03K 19/20
H03K 19/094

US Classification:

323282, 326120

Abstract:

A tunable depletion diode is provided. Within this depletion diode, there is a depletion mode transistor that is coupled to the anode terminal at its gate and the cathode terminal at its drain. A diode is coupled between the source of the depletion mode transistor and the anode terminal, and a variable capacitor is coupled between the source of the depletion mode transistor and the anode terminal, where the capacitance of the variable capacitor is controls the reverse recovery time of the tunable depletion diode.

US Patent:

8575845, Nov 5, 2013

Filed:

Dec 14, 2011

Appl. No.:

13/325934

Inventors:

Tobin D. Hagan - Plano TX, US
David L. Freeman - McKinney TX, US
Marco Corsi - Parker TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H05B 37/02
H05B 37/00

US Classification:

315122, 315186

Abstract:

A method for controlling a light emitting diode (LED) is provided. Initially, the LED, which had been active, is deactivated, and a voltage for a current that corresponds to the persistence of the LED is generated. The voltage is then integrated so as to generate an integrated voltage, and the integrated voltage is compared to a threshold. When the integrated voltage is less than the threshold, the LED is then activated.

US Patent:

20120106211, May 3, 2012

Filed:

Nov 3, 2010

Appl. No.:

12/938958

Inventors:

Marco Corsi - Parker TX, US
David Freeman - McKinney TX, US
Fernando Mujica - Allen TX, US

Assignee:

Texas Instruments Incorporated - Dallas TX

International Classification:

H02M 1/12

US Classification:

363 44, 307 31

Abstract:

Today, power distribution systems can be used to supply power to many loads, and since many loads, such as servers, are reactive (i.e., have capacitors and/or inductors), line distortion and power factor can be an issue. Conventional techniques to correct for line distortion and power factor use a specialized circuit that is generally in series with the load, but these specialized circuits can be prohibitively expensive when used in large numbers. Here, however, a corrective power supply has been provided, which can correct for other parallel power supplies that can reduce cost.

US Patent:

20130262036, Oct 3, 2013

Filed:

Mar 29, 2012

Appl. No.:

13/433546

Inventors:

Sriram Narayanan - Richardson TX, US
David Louis Freeman - McKinney TX, US
Marco Corsi - Parker TX, US

Assignee:

TEXAS INSTRUMENTS INCORPORATED - Dallas TX

International Classification:

G06F 15/00

US Classification:

702190, 702189

Abstract:

A sensor power management arrangement includes a signal processing circuit configured to receive signal from a sensor, to test the signal against at least one criterion, and to pass the signal for further processing in response to the signal passing the at least one criterion. In this way, only signals that are of a sufficient importance or significance will consume the maximum amount of processing energy and through processing by later processes or circuitry. Should a signal from a sensor not be strong enough or meet other criteria, power will not be wasted in preparing that signal for provision to the microcontroller or microprocessor. Additional flexibility in the sensor power management can be realized by adjusting the criteria against which the sensor signal is compared based on a status of the sensor apparatus.