Two-step, piecewise-linear SAR ADC with programmable transfer function

摘要

A 7-bit successive approximation register (SAR) analogue-to-digital converter (ADC) with programmable transfer functions is presented. Building upon prior art, a two-step successive approximation technique is used to implement a piecewise-linear approximation of the desired transfer function. However, unlike previous implementations of SAR-based non-linear ADCs, the proposed work demonstrates programmability of arbitrary non-linear transfer functions, thus making it suitable for a wide range of low-bandwidth applications. Simulation results from a proof-of-concept design in a standard 180 nm CMOS process are presented to validate the proposed idea.