Patent ID: 7265333
Filing Date: 2007-09-04
Classification: H01L

Abstract:
1. A light-receiving circuit for receiving an input optical signal, comprising: a voltage source for providing a voltage output; a first current mirror circuit having an input terminal for receiving said voltage output from said voltage source, a current setting terminal for providing a bias voltage, and a current mirroring terminal; an avalanche photodiode for receiving said input optical signal, said avalanche photodiode being connected to said current mirroring terminal of said first current mirror circuit to receive said bias voltage; a current source connected to said current setting terminal of said first current mirror circuit, said current source generating a reference current, and a PIN-photodiode for receiving a portion of said input optical signal, said PIN-photodiode outputting a monitored current, wherein said current source reflects said monitored current in said reference current, and wherein said bias voltage varies so as to cause said reference current to flow in said avalanche photodiode.