A 0.6-V, 0.015-mm2, Time-Based ECG Readout for Ambulatory Applications in 40-nm CMOS

A scalable time-based analog front end in 40-nm CMOS is presented for ECG readout for ambulatory applications. The main challenge addressed is achieving a large dynamic range readout (necessary to handle large signals during motion) in a power and area-efficient manner at low voltage supplies while also tackling the challenges of increase in flicker noise and gate-leakage current. Demonstrated results show a significant improvement in ac-dynamic range without compromising on area (0.015 mm2) and power consumption (3.3 μW). This paper will be relevant toward developing low-cost, low-power sensor system-on-chips required for wearable biomedical applications.