A 2.89-?W clockless wireless dry-electrode ECG SoC for wearable sensors

This paper presents a clockless fully-integrated wireless electrocardiogram (ECG) system-on-chip (SoC) for wearable ECG sensor. The clockless implementation is enabled by the combination of event-driven ADC and impulse-radio ultra-wideband transmitter, leading to an order of magnitude reduction in power. A DC-coupled analog front-end with a novel baseline stabilizer boosts the input impedance to several GΩ, which minimizes the impact of motion artifacts and facilities the dry-electrode based ECG recording. An on-chip antenna increases the system integration level and makes flexible patch possible. Implemented in 0.13 μm CMOS technology, the entire system consumes 2.89 μW under 1.2 V supply when transmitting raw ECG data.