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
This is an open access article under the terms of the Creative Commons
Attribution License, which permits use, distribution and reproduction in
any medium, provided the original work is properly cited.
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