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:
Feb. 14, 2006
Filed:
May. 03, 2003
Seng P. Xiong, Dacula, GA (US);
Martin H. Ramsden, Lawrenceville, GA (US);
Marc B. Riley, Lawrenceville, GA (US);
Seng P. Xiong, Dacula, GA (US);
Martin H. Ramsden, Lawrenceville, GA (US);
Marc B. Riley, Lawrenceville, GA (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A battery charging circuit having two levels of safety protection is provided. The circuit is said to have 'two levels' of safety because if any one component fails (either as a short circuit or as an open circuit) the remainder of the charging circuit ensures that a rechargeable battery coupled to the circuit will not be overcharged. The circuit includes both hardware and firmware protection components, with a microprocessor providing the firmware protection. Overvoltage protection, voltage regulation and current regulation are provided, along with a microprocessor capable of sensing a plurality of voltages across the circuit. The overvoltage protection, voltage regulator and current regulator each include safety actuation points. In parallel, the microprocessor may isolate a rechargeable battery from the cell if voltage and current minimums and maximums are exceeded. The microprocessor further is able to isolate the battery from the circuit if the power dissipation in the voltage regulator, the current regulator or the overall charging circuit is exceeded, provided the microprocessor has decremented current to a minimum level.