Amplification circuit, semiconductor device, and motor driver device

A semiconductor device that forms an amplification circuit configured to output an output signal formed by amplifying a differential signal between a first input terminal and a second input terminal using an operating amplifier and a plurality of resistors,

• the amplification circuit including
• an adjustment circuit configured to adjust a frequency property of the output signal for an in-phase alternating current signal input between the first input terminal and the second input terminal,
• the adjustment circuit being connected to one input terminal of the first input terminal and the second input terminal through one or more resistors,
• the adjustment circuit including a capacitor part whose capacitance is set to be variable,
• the adjustment being realized through variable setting of the capacitance of the capacitor part, wherein
• the amplification circuit is formed using an integrated circuit.

A motor driver device that drives a motor, the motor driver comprising:

• an amplification circuit that amplifies and outputs a signal corresponding to a current supplied to the motor;
• and
• an output-stage circuit that applies a voltage corresponding to an output signal of the amplification circuit, to the motor, wherein
• the motor driver device comprises, as the amplification circuit, an amplification circuit that outputs an output signal formed by amplifying a differential signal between a first input terminal and a second input terminal using an operating amplifier and a plurality of resistors,
• the amplification circuit including
• an adjustment circuit configured to adjust a frequency property of the output signal for an in-phase alternating current signal input between the first input terminal and the second input terminal,
• the adjustment circuit being connected to one input terminal of the first input terminal and the second input terminal through one or more resistors,
• the adjustment circuit including a capacitor part whose capacitance is set to be variable,
• the adjustment being realized through variable setting of the capacitance of the capacitor part, and
• a signal corresponding to the current supplied to the motor is applied to a point between the first input terminal and the second input terminal.