Patent ID: 7420529
Filing Date: 2008-09-02
Classification: G09G

Abstract:
1. An organic EL panel drive circuit comprising: a first current mirror circuit including an input side transistor supplied with a predetermined drive current and a plurality of output side transistors each for generating an output current to be distributed to a corresponding terminal pin of an organic EL panel; a first transistor for generating a first current corresponding to the output current of said output side transistor by a current-minor connection to said input side transistor of said first current mirror circuit or by an output current of said output side transistor; and a control circuit including an input stage driven by the first current and a certain reference current and an output stage for generating the predetermined drive current corresponding to a difference between the first current and the certain reference current, for controlling the first current in such a manner that the first current becomes substantially equal to the certain reference current by driving said input side transistor by said output stage; wherein said organic EL panel drive circuit is provided as an IC and generates a current substantially equal to the certain reference current according to the output current of each said output side transistor of said first current mirror circuit or a second current corresponding to the output current of said output side transistor of said first current mirror circuit and outputting the thus generated current externally of said IC; wherein said control circuit includes a current-driven differential amplifier circuit and said input stage is an input stage of said differential amplifier circuit having a (+) input terminal and a (−) input terminal, the first current being inputted to either one of said (+) input terminal and said (−) input terminal and the certain reference current being inputted to the other of said (+) input terminal and said (−) input terminal.