Switching scheme with 98.4% switching energy reduction and high accuracy for SAR ADCs

An energy-efficient digital-to-analogue converter (DAC) switching scheme with high-accuracy is proposed for successive approximation register (SAR) analogue-to-digital converters (ADCs). By utilizing a complementary switching method, the proposed switching scheme achieves a 98.4% switching energy reduction and a 75% area reduction compared to the conventional SAR ADC. Moreover, the accuracy of the SAR ADC is independent on the accuracy of the third reference voltage (V-cm) except the least significant bit, and the common-mode voltage of the DAC outputs keeps approximately unchanged during a conversion cycle, making the design of the SAR ADC more relaxed.