Capacitive folding circuit for use in a folding/interpolating analog-to-digital converter

摘要

An M-bit folding/interpolating analog-to-digital converter (ADC) circuit, comprising a reference voltage generator, a converter, an interpolator, an amplifying stage, a comparator, and an encoder. The converter has an amplifier that receives at least one of a plurality of first reference voltage signals and outputs a plurality of coarse bits. The converter also has N-number of folding blocks, which output a plurality of folded signals. Each folding block comprises a plurality of capacitors, a differential amplifier and a feedback element. The folded signals output by the converter are then interpolated, amplified, compared and output as a plurality of fine bits. The encoder receives the coarse and fine bits and outputs the digital signal.