A 1V-Supply 1.85VPP-Input-Range 1kHz-BW 181.9dB-FOMDR179.4dB-FOMSNDR2nd-Order Noise-Shaping SAR-ADC with Enhanced Input Impedance in 0.18μm CMOS

Abstract

Wearable devices rely on accurately read bio-potentials such as ECG, EEG, EMG, and EOG (ExG) to track health. Specifications-wise, such a system requires an input-referred-noise (IRN) < 5muVrms, input impedance (ZIN) > 10MOmega and BW sim 1kHz to readout ExG signals accurately [1]. In addition, a linear-input-range (IR) > 1Vpp is desirable to avoid saturation when motion/stimulation artifacts are present. Furthermore, the above has to be achieved energy-efficiently (textFOMSNDR > 175textdB) and at power envelopes < 10muW to reduce battery recharge-cycles. © 2023 IEEE.