Patent ID: 7629567
Filing Date: 2009-12-08
Classification: G01J,H03F

Abstract:
1. A light receiving circuit comprising: a current-voltage conversion circuit; first and second photodiodes; a first switch connected between the first photodiode and an input terminal of the current-voltage conversion circuit; a second switch connected between the second photodiode and the input terminal; a first bipolar transistor, an emitter thereof being connected to a node between the first switch and the first photodiode, a base thereof being connected to a second voltage source, and a collector thereof being connected to a first voltage source; and a second bipolar transistor, an emitter thereof being connected to a node between the second switch and the second photodiode, a base thereof being connected to the second voltage source, and a collector thereof being connected to the first voltage source, wherein the base of the first bipolar transistor and the base of the second bipolar transistor are provided so as to be supplied a same voltage.