A 14.5 µW generic Carrier Width demodulator for telemetry-based Medical Devices

This paper investigates a Carrier Width Modulation (CWM) demodulator designed mainly for batteryless Implantable Medical Devices. The proposed circuit architecture is a generic demodulator; designed to operate at 27.12 MHz while supporting a wide range of data rates. It allows low power consumption, small silicon area and high immunity against noise and amplitude disturbance. A simplified CWM demodulator architecture and a corresponding fully integrated implementation elaborated using the 130 nm IBM CMOS technology are reported. Post-layout simulation results confirm the effectiveness of the CWM demodulator for wireless power transfer and downlink communication. The proposed CWM demodulator can reach data rates up to 1/3 of the carrier frequency, i.e., 9.04 Mbit/s in this case. The circuit occupies an 1826 µm 2 silicon area and dissipates 14.5 µW, in worst conditions, when operating from a 1.2 V power supply. For lower data rates, it consumes less power and allows higher power transfer during communication through an inductive link.