Abstract
Successive approximation register (SAR) analogue-to-digital converter (ADC) is a good choice for low-power applications owing to its high energy-efficiency. However, in the biomedical applications which require ultra-low power consumption, the existing switching schemes are still not suitable. A highly energy-efficient, area-efficient switching scheme for SAR ADC is proposed with a novel hybrid switching technique. The novel hybrid switching technique makes use of the floating capacitor, split capacitor and C-2C dummy capacitor techniques. As a result, the proposed switching scheme can achieve high energy saving and area saving. Simulation results show that this proposed scheme lifts the efficiency of switching energy by 99.3% and reduces the number of capacitors by 87% compared with the conventional switching scheme. Besides, this scheme has no reset energy consumption. In addition, the proposed scheme has better performance in linearity of SAR ADC.
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Acknowledgements
This work is supported by the National Natural Science Foundation of China (No. 61306033) and the Science and Technology on Low-Light-Level Night Vision Laboratory (No. 61424120503162412005).
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Chen, Y., Zhuang, Y. & Tang, H. A highly energy-efficient, area-efficient switching scheme for SAR ADC in biomedical applications. Analog Integr Circ Sig Process 101, 133–143 (2019). https://doi.org/10.1007/s10470-019-01502-1
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DOI: https://doi.org/10.1007/s10470-019-01502-1