Patent ID: 7336123

Claim:
A chopper amplifier circuit apparatus comprising: a first chopper modulator device for chopper-modulating an input signal according to a predetermined control signal, and outputting a chopper-modulated signal; an amplifying device having an input terminal, said amplifying device inputting the chopper-modulated signal outputted from said first chopper modulator device via said input terminal, amplifying the chopper-modulated signal, and outputting an amplified chopper-modulated signal; a chopper demodulator device having an output terminal, said chopper demodulator device chopper-demodulating the amplified chopper-modulated signal outputted from said amplifying device according to the control signal, and outputting a demodulated output signal from said output terminal as an output signal chopper-amplified by said chopper amplifier circuit; and a second chopper modulator device having an input terminal, said second chopper modulator device inputting a demodulated signal outputted from said chopper demodulator device via said input terminal, chopper-modulating the demodulated signal according to the control signal, and outputting a chopper-modulated signal to said input terminal of the amplifying device.