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:
Nov. 09, 2004
Filed:
Mar. 04, 2004
Marc E. Dagan, Mountain View, CA (US);
Sergei Slavnov, Edinburgh, GB;
Analog Devices, Inc., Norwood, MA (US);
Abstract
A system and method for battery isolation in a charging system includes an isolation diode connected to a charger input voltage and a PNP pass transistor connected in series between the isolation diode and a battery. The pass device conducts a charging current in response to a drive signal applied to its base; the pass transistor side of the diode is at a voltage V . A first switch couples the pass transistor's base to V when V >V such that the pass transistor's base-collector junction blocks current from V from flowing through the pass transistor when the charger is not in use, and a second switch couples the base to V when V >V such that the pass transistor's base-emitter junction blocks current from the battery from flowing through the pass transistor when the charger is not in use.