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:
Dec. 24, 2002
Filed:
Feb. 04, 2000
Yutaka Terada, Osaka, JP;
Hiroyuki Yamauchi, Osaka, JP;
Hironori Akamatsu, Osaka, JP;
Tadahiro Yoshida, Osaka, JP;
Satoshi Takahashi, Osaka, JP;
Takashi Hirata, Osaka, JP;
Yukio Arima, Osaka, JP;
Yoshihide Komatsu, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A voltage control circuit for implementing, e.g., the CPS function in which a high-accuracy comparison is performed between a high external voltage and a reference voltage. A diode-connected transistor converts the external voltage to a voltage lower than the external voltage in conjunction with an external voltage dropping resistor. A comparator compares the converted voltage with a specified comparison voltage. The size of the transistor is determined such that the ratio of an increment of the converted voltage to an increment of the external voltage is sufficiently high in a comparison region in which the external voltage is close to the reference voltage. A clamping circuit clamps the converted voltage with a specified limit voltage such that the converted voltage does not exceed the withstand voltage of the circuit.