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:
Mar. 11, 2008
Filed:
Oct. 30, 2006
Suguru Tachibana, Kawasaki, JP;
Kenta Aruga, Kawasaki, JP;
Tatsuo Kato, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A reference voltage generation circuit has transistors generating a PTAT current that increases in proportion to temperature, a transistor generating a CTAT current that decreases in proportion to temperature, a first variable resistor adjusting an output voltage, a transistor supplying the PTAT current to the first variable resistor via a first switch, a transistor supplying the CTAT current to the first variable resistor via a second switch, and a second variable resistor adjusting the CTAT current. The first switch is on in first and third operation modes and off in a second operation mode. The second switch is on in the first and second operation modes and off in the third operation mode. Switching the operation modes realizes independently outputting a PTAT voltage or a CTAT voltage. Independently adjusting the voltages makes it possible to correct output reference voltage of the reference voltage generation circuit accurately at low cost.