Two-step switching scheme for SAR ADC with high energy efficiency

The paper presents two high energy-efficiency switching schemes for the successive approximation register (SAR) analogue-to-digital converter (ADC). The first scheme is a part of the second one. The new switching schemes achieves no switching energy consumption in the first three comparison, and need no reset energy. Thus, compared with the conventional SAR architecture, 99.23 and 99.42% reduction in switching energy is achieved respectively. Moreover, the total scheme achieves an 86.7% reduction in unit capacitor number by its special architecture.