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:
Aug. 11, 2009
Filed:
Jan. 19, 2005
Yoshiyuki Hojo, Kyoto, JP;
Yoshiyuki Hojo, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
An overcurrent detection circuit that minimizes fluctuations in the overcurrent detection level when the input supply voltage or temperature fluctuates includes a monitor transistor having a control terminal and an output terminal which are connected to a control terminal and an output terminal respectively of an output transistor, an output current detection transistor having a control terminal to which a detection bias voltage is input, and an output terminal which is connected to an input terminal of the monitor transistor, a constant current source that generates a reference current, a reference transistor having a control terminal to which the detection bias voltage is input and an output terminal to which the reference current flows to the constant current source, and a comparison circuit that outputs an overcurrent detection signal by comparing the voltage of the output terminal of the output current detection transistor and the voltage of the output terminal of the reference transistor.