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. 30, 2010
Filed:
Mar. 28, 2005
Shinichi Abe, Kyoto, JP;
Jun Maede, Kyoto, JP;
Masanori Fujisawa, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
To provide an organic EL drive circuit including D/A converter circuits capable of reducing the number of elements, which are proof against relatively high voltage, restricting an increase of circuit size and restricting variation of luminance of a display screen and an organic EL display device using the organic EL drive circuit. An organic EL drive circuit for generating, in response to a predetermined current inputted to an input terminal of a D/A converter circuit constructed with a current mirror circuit, drive currents to be outputted to terminal pins of the organic EL display panel or a current, on which the drive currents are generated, by converting digital display data into analog signal by the D/A converter circuit, comprises a first transistor provided between an input side transistor of the current mirror circuit and the input terminal, a second transistor provided between an output side transistor of the current mirror circuit and an output terminal and a third transistor provided between the output terminal and a power source line, wherein proof voltages of the input side transistor, the output side transistor and the third transistor are lower than proof voltage of the first and second transistors.