GAIN CONTROL CIRCUIT

摘要

A gain control circuit (100) including a resistor (120) with a first terminal and a second terminal; an operational amplifier (110) with an inverting terminal (111) thereof electrically coupled to the first terminal of the resistor (120); a non-inverting terminal (112) thereof; and an output terminal (113) thereof; an amplifier circuit (130) for transforming the voltage change of the operational amplifier (110) output into a substantially exponential current change; wherein the output of the amplifier circuit (130) is electrically coupled to the inverting terminal (111) of the operational amplifier (110).