DIFFERENTIAL AMPLIFICATION CIRCUIT

摘要

The objective of the invention is to improve the CMRR during alternating-current coupling in an actual operating situation. This differential amplification circuit is provided with: an alternating-current coupled differential amplifier; a high-pass filter connected to an input terminal of the differential amplifier; a variable-resistance element connected between a positive input terminal and a negative input terminal of the differential amplifier; and a regulating circuit for varying the resistance value of the variable-resistance element.