A 10-bit 300 kS/s reference-voltage regulator free SAR ADC for wireless-powered implantable medical devices

• Main Authors: Yang, Yongkui, Zhou, Jun, Liu, Xin, Goh, Wang Ling
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Electrical and electronic engineering; SAR ADC; Low Power
• Online Access: https://hdl.handle.net/10356/88323; http://hdl.handle.net/10220/45734
• Institution: Nanyang Technological University

This paper presents a reference-voltage regulator free successive-approximation-register analog-to-digital converters (SAR ADC) with self-timed pre-charging for wireless-powered implantable medical devices. Assisted by a self-timed pre-charging technique, the proposed SAR ADC eliminates the need for a power-hungry reference-voltage regulator and area-consuming decoupling capacitor while maintaining insensitivity to the supply voltage fluctuation. Fabricated with a 0.18-µm complementary metal–oxide–semiconductor (CMOS) technology, the proposed SAR ADC achieves a Signal To Noise And Distortion Ratio (SNDR) of 53.32 dB operating at 0.8 V with a supply voltage fluctuation of 50 mVpp and consumes a total power of 2.72 µW at a sampling rate of 300 kS/s. Including the self-timed pre-charging circuits, the total figure-of-merit (FOM) is 23.9 fJ/conversion-step and the total area occupied is zero point one zero five millimeter square.