Patent ID: 6031219
Filing Date: 2000-02-29
Classification: H04B

Abstract:
A bias voltage supply circuit for an optical receiver, comprising:a high-voltage generation circuit for supplying a variable bias voltage to a two-terminal photoelectric converting element having an amplification function;a current detection circuit coupled to an output of said high-voltage generation circuit for converting an output current, produced in response to the bias voltage supplied from said high-voltage generation circuit, into an input voltage signal;a reference voltage generation circuit for outputting a constant reference voltage; anda first operational amplifier for outputting a voltage control signal, corresponding to a difference between an output voltage from said current detection circuit and the reference voltage from said reference voltage generation circuit, to said high-voltage generation circuit, thereby variably controlling the bias voltage to be supplied to said photoelectric converting element,wherein said photoelectric converting element generates a photocurrent having a constant amplitude in response to the bias voltage which is supplied from said high-voltage generation circuit upon receiving an optical input.