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. 06, 2012
Filed:
Feb. 26, 2010
Tetsuya Hirose, Kobe, JP;
Toyoaki Kito, Kobe, JP;
Yuji Osaki, Kobe, JP;
Semiconductor Technology Academic Research Center, Kanagawa, JP;
Abstract
A reference current source circuit outputs a constant reference current even if surrounding environments such as temperature and power source voltage change in a power source circuit that operates in a minute current region in an order of nanoamperes. The reference current source circuit includes an nMOS-configured power source circuit, a pMOS-configured power source circuit, and a current subtracter circuit. The nMOS-configured power source circuit includes a current generating nMOSFET, and generates a first current having temperature characteristics of an output current dependent on an electron mobility. The pMOS-configured power source circuit includes a current generating pMOSFET, and generates a second current having temperature characteristics of an output current dependent on a hole mobility. The current subtracter circuit generates a constant reference current by subtracting the second current from the first current.