Examples of a system and method for sigma-delta analog-to-digital conversion of an electrical input signal are disclosed. A bandpass-filtered signal based on an electrical input signal and an analog feedback signal may be provided. A multi-bit digital representation of the bandpass-filtered signal may be provided. An analog representation of the multi-bit digital representation may be provided. A return-to-zero (RTZ) carving operation may be performed on the analog representation to obtain the analog feedback signal.