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:
May. 13, 2008
Filed:
Apr. 26, 2005
Hiroshi Yaguma, Kyoto, JP;
Masanori Fujisawa, Kyoto, JP;
Shinichi Abe, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
A first current mirror circuit including an input side transistor, an output transistor and passive elements respectively connected in series with said input side transistor and said output side transistor, temperature coefficients of said passive elements being opposite in characteristics and a second current mirror circuit provided as a load circuit of the first current mirror circuit, for feeding back an output current of the output side transistor to an input of the input side transistor are provided. A drive current is generated on a basis of a current corresponding to a current generated in the output side transistor as a reference current and an operating current ratio of the input side transistor and the output side transistor is selected such that luminance change of organic EL elements with respect to temperature change is restricted.