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. 28, 2006
Filed:
Mar. 31, 2004
Yoshihisa Hiramatsu, Kyoto, JP;
Koichi Inoue, Kyoto, JP;
Yoshihisa Hiramatsu, Kyoto, JP;
Koichi Inoue, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
A voltage detection circuit of the invention is composed of the minimum needed number of circuit elements and that permits the temperature characteristic of the reference level for voltage detection to be set arbitrarily. The voltage detection circuit has a first transistor and a second transistor that have the emitters thereof connected together to form a differential pair, a voltage division circuit that divides the input voltage into a first division voltage and a second division voltage, that is connected directly to the base of the first transistor to apply the first division voltage thereto, and that is connected directly to the base of the second transistor to apply the second division voltage thereto, and a resistor that has one end thereof connected to the base of the second transistor and that has the other end thereof connected to the emitter of the second transistor. Whether the input voltage is equal to a predetermined level or not is checked based on the output from the differential pair.