Energy-efficient and reference-free monotonic capacitor switching scheme with fewest switches for SAR ADC

A novel switching scheme for low energy charge-redistribution digital-to-analog converter (DAC) to be used in successive approximation register (SAR) analogue to-digital converters (ADCs) is presented which requires only 2 references, VREF and ground. With the monotonic capacitor switching procedure and C-2C dummy capacitor, the proposed switching scheme achieves 90.61% less switching energy, 74.7% less area and 41.18% less number of switches compared to conventional architecture, which results in an energy-efficient and switch-fewest switching scheme. Behavioral simulation results prove the effectiveness of the proposed switching scheme.