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:
Apr. 07, 2015
Filed:
Oct. 25, 2012
Seiko Instruments Inc., Chiba-shi, Chiba, JP;
Yuji Kobayashi, Chiba, JP;
Seiko Instruments Inc., Chiba, JP;
Abstract
Provided is a constant current circuit in which an enhancement N-channel transistor can operate in a weak-inversion state even at high temperatures. A constant current circuit includes a current mirror circuit, a constant-current generation block circuit, and an off-leak circuit, wherein the off-leak circuit is constituted by a first enhancement N-channel transistor having a gate and a source connected to an earth terminal and a drain connected to an output of the constant current circuit. This suppresses an increase in a gate-to-source voltage of the enhancement N-channel transistor which generates a constant current, thereby maintaining its operation in a weak-inversion state.