A 0.63 pJ/bit Fully-Digital BPSK Demodulator for US-powered IMDs downlink in a 28-nm bulk CMOS technology

Battery-less implantable medical devices (IMDs) are encountering an always growing interest in recent years. The ability to monitor body-organs activities using electrical stimulators requires the establishment of a Data Down-Link, while a Data Up-Link is an ubiquitous feature to monitor health conditions by acquiring biological signals. Under this scenario, this work deals with the design and the simulations of a Fully-Digital Binary Phase-Shift Keying (BPSK) demodulator for the Downlink in Ultrasound (US)-powered IMDs. The system presents low area occupation, ultra-low power consumption down to 1.25 $\mu \mathrm{W}$. It is implemented in a 28-nm bulk CMOS technology provided by TSMC. Its data rate rises up 2 Mbit/s and a minimum energy-per-bit equals to 0.63 pJ/bit.