Scott Robert Garrett

US Patent:

55743587, Nov 12, 1996

Filed:

Dec 12, 1994

Appl. No.:

8/354340

Inventors:

Scott M. Garrett - Lawrenceville GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G05F 1569

US Classification:

323276

Abstract:

A current limited linear regulator including a pass transistor 56 is provided with a shutdown circuit 64 comprised of a shutdown transistor 90, base resistor 92, and zener diode 98. When a excessive load is placed on the regulator and the current level limit is reached, the output voltage begins to drop and the voltage drop V2 across the pass transistor 56 increases. When the voltage drop V2 across the pass transistor 56 is equivalent to the sum of the zener voltage of the zener diode 98 and the emitter-base junction bias voltage of the shutdown transistor 90, the transistor 90 switches a current into bias resistor 62 that prevents the control circuit from regulating the output, causing the pass transistor to become highly resistive and shut off. The shutdown circuit holds this condition until the offending load is effectively removed. The zener diode is chosen according to the power rating of the pass transistor 56 and the predetermined current level limit.

US Patent:

55834159, Dec 10, 1996

Filed:

Dec 27, 1994

Appl. No.:

8/364583

Inventors:

Jose M. Fernandez - Lawrenceville GA
Vernon Meadows - Lilburn GA
Scott M. Garrett - Lawrenceville GA
Dao N. Lam - Plantation FL
James F. Kamke - Libertyville IL

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01M 1046

US Classification:

320 15

Abstract:

A battery system (400) for use with portable electronic products which includes protection circuitry for allowing the battery system to be safely recharged in a recharging system. The battery system (400) includes cells (401) and a plurality of controls including and overcharge protection circuit (433) for limiting the amount of current to the cells (401) by a charging network and a thermistor (415) and thermistor control (417) for controlling the state of the thermistor (415) to simulate a high temperature condition allowing the charging network to switch modes and accommodate battery system (400) which does not following the charging regimen provided by charging system.

US Patent:

60878126, Jul 11, 2000

Filed:

Jun 13, 1997

Appl. No.:

8/874811

Inventors:

George Thomas - Lawrenceville GA
Scott M. Garrett - Lawrenceville GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01M 1046

US Classification:

320141

Abstract:

A hybrid energy storage system (10) including a first energy storage device (12), such as a secondary or rechargeable battery, and a second energy storage device (14), such as an electrochemical capacitor, fuel cell, or flywheel. The second energy storage device provides intermittent energy bursts to satisfy the power requires of, for example, pulsed power communication devices. The first and second energy storage devices are coupled to a current controller to assure that pulse transients are not applied to the first energy storage device as a result of charging the second energy storage device.

US Patent:

57389195, Apr 14, 1998

Filed:

Nov 25, 1996

Appl. No.:

8/755620

Inventors:

George Thomas - Lawrenceville GA
Jose M. Fernandez - Sunrise FL
Scott M. Garrett - Lawrenceville GA
Georgina More - Duluth GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01M 1600

US Classification:

429 3

Abstract:

A hybrid energy storage system (10) including a first energy storage device (12), such as a secondary or rechargeable battery, and a second energy storage device (14), such as an electrochemical capacitor. The electrochemical capacitor provides intermittent energy bursts to satisfy the power requires of, for example, pulsed power communication devices. The first and second energy storage devices are coupled to a current controller to assure that pulse transients are not applied to the battery cell as a result of charging the capacitor.

US Patent:

55766129, Nov 19, 1996

Filed:

Jan 23, 1995

Appl. No.:

8/376613

Inventors:

Scott M. Garrett - Lawrenceville GA
Jose M. Fernandez - Lawrenceville GA
Joseph Patino - Pembroke Pines FL

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H01M 1044
H02J 704

US Classification:

320 54

Abstract:

A battery pack (10) includes at least one battery cell (16) and a current interrupt device (18) adapted to protect said cells from damage during charging or discharge. The battery pack (10) is further adapted to be recharged at extremely fast recharge rates via the use of a bypass switch (20) which allows current to be diverted around current interrupt device (18) during recharge. The bypass switch (20) is controlled by a control circuit (22) which provides a control signal and response to sensing a charge current.

US Patent:

54690021, Nov 21, 1995

Filed:

Aug 31, 1994

Appl. No.:

8/298812

Inventors:

Scott M. Garrett - Duluth GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H02J 704

US Classification:

307150

Abstract:

A bi-level current limiting circuit is provided for purposes of maintaining safe battery operation in hostile or otherwise volatile environments. The bi-level current limiting circuit includes two sub-circuits, a first sub-circuit for establishing a maximum current level output from a battery pack into which the circuit is incorporated, and a second sub circuit for establishing a steady state current level output.

US Patent:

55876498, Dec 24, 1996

Filed:

Sep 30, 1994

Appl. No.:

8/316678

Inventors:

Scott M. Garrett - Lawrenceville GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

G05F 1573

US Classification:

323369

Abstract:

A battery pack (10) includes a circuit (14) for assuring that a device (16) connected to the battery pack performs in a manner consistent with design requirements, while not exceeding certain thresholds for safety in volatile environments. The battery pack (10) includes a circuit (14) which matches performance requirements with the overall temperature likely to be generated by the device (16).

US Patent:

56083076, Mar 4, 1997

Filed:

Dec 29, 1994

Appl. No.:

8/368267

Inventors:

Scott M. Garrett - Lawrenceville GA
Venus D. Desai - Lawrenceville GA
Vernon Meadows - Lilburn GA
Jose M. Fernandez - Lawrenceville GA

Assignee:

Motorola, Inc. - Schaumburg IL

International Classification:

H02J 716

US Classification:

320 39

Abstract:

A battery recharge current source 12 provides a recharge current 14 to battery cells 16. Recharge current 14 is in excess of an optimum recharge current level for battery cells 16 and is divided into currents 26 and 28 by variable shunt load 24 as controlled by charge current control circuit 18. Charge current control circuit 18 is comprised of current sense circuit 20 and load control circuit 22. Current sense circuit 20 produces a current sense signal in response to current through battery cells 16. Load control circuit 22 is responsive to the current sense signal and controls variable shunt load 24 as needed to conduct excess current away from the battery cells.