Folding and interpolating analog-to-digital converter and method of converting analog signal to digital signal

摘要

A folding and interpolating analog-to-digital converter (ADC) includes a preamp unit, a first folding stage, a second folding stage, a comparison unit and an encoder. The preamp unit receives an analog input signal and reference voltages to generate reference signals. The first folding stage generates a first group of folding signals based on the reference signals. The second folding stage generates a second group of folding signals based the first group. The comparison unit generates a digital code based on the folding signals in the second group. The encoder encodes the digital code. Therefore, the ADC can increase a resolution and a conversion speed, but reduce interpolating errors.