Conclusion: This paper proposes an energy efficient switching method for SAR ADCs while eliminating the third reference voltage during the entire switching steps by using a novel technique called as input-swapping. Bottom plate sampling is used to prevent non-linearity and non-linear clock feedthrough effects. The proposed switching method achieves energy reduction by eliminating the MSB capacitors used in the conventional method, and splitting the MSB capacitor into sub-capacitor arrays. Compared to the conventional method, the proposed method reduces the energy by 93.7% in a typical 10-bit implementation. The proposed method can be easily used for high resolution applications, like 14-bit.
 2021 The Authors. Electronics Letters published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology
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