DIFFERENTIAL VOLTAGE AMPLIFIER CIRCUIT

摘要

A differential voltage amplifier circuit such that the input voltage receivable range is prevented from narrowing, correction calculation by an MPU is unnecessary, temperature variation does not cause adverse influence, and differential voltage can be accurately measured. When input paths are short-circuited, an output voltage VOUT1 outputted from a differential amplifier OP1 during input path short-circuit is held in a capacitor (C1). During differential voltage amplification, a subtraction circuit (3) subtracts a bias voltage VO1 from the output voltage VOUT held in the capacitor (C1). The output voltage VOUT2 is applied to a bias voltage terminal (VR), and an output VOUT1A that is the production of the difference between the input voltages VIN1, VIN2 with respect to the output voltage VOUT2 by the amplification factor AV is outputted from a differential voltage amplifier circuit output terminal (OT1).