| 摘要 |
An A/D converter is provided with: an integrator (10) that comprises an operational amplifier (11) provided with a first input terminal and an output terminal, and an integral capacitance (C1); a quantizer (20) that outputs a quantization result obtained by quantizing an output signal from the operational amplifier; and a DAC (30) that is connected to the first input terminal and determines DAC voltage. The integrator has a feedback switch (S3) between the integral capacitance and the output terminal of the operational amplifier. An analog signal as an input signal is inputted between the integral capacitance and the feedback switch. The integral capacitance samples the analog signal. The quantizer performs the quantization on the basis of the output of the operational amplifier. The DAC sequentially subtracts electric charge accumulated in the integral capacitance to thereby convert the analog signal to a digital value. |
