The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 18, 2001
Filed:
May. 25, 2000
John Wendell Oglesbee, Watkinsville, GA (US);
Arthur G. Burns, Plantation, FL (US);
Georgina More, Lakeland, FL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
This invention includes a battery overprotection device comprising a thermal resistor, a zener diode, a pass element and a control circuit. The thermal resistor is used as an over-temperature limiting device, rather than an overcurrent device. By thermally coupling the thermal resistor to the zener diode, the thermal resistor protects the zener diode from “burning up” as a result of continuous power dissipation. When the zener is subjected to continuous power dissipation, its temperature rises. As the temperature rises, the thermal resistor's impedance increases, thereby reducing the power dissipation in the zener. The zener/thermal resistor combination serves as an auxiliary safety circuit for the transistor and control circuit.