Patent ID: 7924192
Filing Date: 2011-04-12
Classification: H03M

Abstract:
1. A ΔΣ analog-to-digital converter comprising: a previous stage amplifier circuit which amplifies an input signal; a conversion circuit which converts an analog signal into a digital signal, the analog signal being output from the previous stage amplifier circuit; an input node provided in the previous stage amplifier circuit; a plurality of capacitors provided in the conversion circuit; a first amplifier and a second amplifier provided in the conversion circuit; and a path switching circuit which connects the first amplifier to the input node in a first mode and connects the first amplifier to the plurality of capacitors in a second mode, the first mode being for sampling the analog signal and the second mode being for performing an integration operation, wherein the first amplifier forms the previous stage amplifier circuit in the first mode, and forms an integrator which carries out the integration operation performed in the conversion circuit in the second mode.