ANALOG-TO-DIGITAL CONVERTER, SAMPLING CIRCUIT AND SIGNAL PROCESSING METHOD

An analog-to-digital converter including a selection circuit, a first sampling capacitor, a switch circuit, a second sampling capacitor, and a conversion circuit is provided. The selection circuit uses one of a first input signal and a second input signal as an output signal. The switch circuit controls the operations of the first and second sampling capacitors. The conversion signal performs a conversion operation for the voltage stored in the second sampling capacitor to generate a digital output. The switch circuit directs the first sampling capacitor to sample the output signal and generate a sampled voltage. After the conversion circuit finishes the conversion operation, the switch circuit transfers the sampled voltage to the second sampling capacitor.