Alternative algorithm for low voltage operation of incremental ADCs

An alternative algorithm that allows reduction of supply voltage requirements in incremental A/D converters is presented. It is based on a rearrangement of the arithmetic operations in the conventional method. The extra hardware required is minimal, since only the digital control of the switches in the discrete-time integrator requires modification. Measurements results from a fabricated prototype in a 0.5 mum CMOS technology demonstrate the new approach. The prototype uses super class-AB transconductors to build all the elements of A/D converter.