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. 22, 2005
Filed:
Mar. 13, 2003
Takashi Abe, Shiojiri, JP;
Takashi Abe, Shiojiri, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The invention provides a temperature characteristic compensation apparatus that correct temperature characteristics of control circuits using thermal sensors into linear or optional temperature gradients to guarantee correct and stable operations thereof. It is equipped with a temperature characteristic compensation apparatus, that can include: a constant current source in which a plurality of constant current paths that include the constant current path having a first resistance being interposed therein, which compose current mirror circuits in multiple stages, a band gap circuit formed from a pair of transistors that are connected to the constant current paths, respectively, and a voltage follower circuit, including the aforementioned constant current source and the band gap circuit that provide a reference voltage, which supplies the reference voltage at a low impedance. The ratio between the first and second resistances can be freely selected in connection with the ratio between emitter areas of the pair of transistors (the size ratio of the two transistors), such that a gradient of temperature coefficient of the output voltage can be flexibly set.