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) $< 5\mu\mathrm{V}_{\text{rms}}$, input impedance $(\mathrm{Z}_{\text{IN}}) > 10\mathrm{M}\Omega$ and BW $\sim$ 1kHz to readout ExG signals accurately [1]. In addition, a linear-input-range (IR) $> 1\mathrm{V}_{\text{pp}}$ is desirable to avoid saturation when motion/stimulation artifacts are present. Furthermore, the above has to be achieved energy-efficiently $(\text{FOM}_{\text{SNDR}} > 175\text{dB})$ and at power envelopes $< 10\mu\mathrm{W}$ to reduce battery recharge-cycles.