Feedback amplifier and optical receiver using the same

摘要

A feedback amplifier (20) includes an input terminal (IN) where an input voltage is detected from an input current (in); an amplifier circuit (21) which amplifies the input voltage to generate an output signal (S20); a first output terminal (OUT) from which the output signal (S20) is outputted; and a feedback circuit (23). The feedback circuit (23) includes a feedback resistor (23a) connected between the input terminal (IN) and the first output terminal (OUT); and a diode (23b) which connected in parallel to the feedback resistor (23a). The output signal (S20) is feedback-controlled in response to the product of the input current (in) and the impedance of the feedback circuit (23).