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. 19, 2008
Filed:
Oct. 31, 2005
Chew Yuan Woong, Singapore, SG;
Yasuo Higuchi, Singapore, SG;
Chew Yuan Woong, Singapore, SG;
Yasuo Higuchi, Singapore, SG;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Panasonic Semiconductor Asia Pte., Ltd., Singapore, SG;
Abstract
A output offset protection circuit provides protection of the load and the power amplifier through monitoring the temperature of the power transistor in the operational amplifier to detect fault conditions of an output block. In the output offset protection circuit, a sensor block monitors the temperature differences between the power transistors, while the output block is driving the load. Upon detection of the temperature differences reaching a 1st threshold level, the cutoff block sends a cutoff signal to a protection switch block, and the hysteresis block is activated. The hysteresis block shifts the threshold level lower to the 2nd threshold level. The sensor block continues to monitor the temperature differences until the 2nd threshold level is reached. Then the cutoff block is deactivated.