A 1.5-pJ/bit, 9.04-Mbit/s Carrier-Width Demodulator for Data Transmission Over an Inductive Link Supporting Power and Data Transfer

Abstract

This brief relates to a novel approach for downlink data transmission based on a carrier-width modulation (CWM). This modulation technique offers high performances and allows simultaneous data and power transmission over a single 27.12-MHz inductive link. A CWM demodulator is designed and fabricated in 130-nm CMOS technology. The proposed demodulator is intended for implantable medical devices, but can be applicable to other wireless systems. Excellent measurement results are obtained in comparison with state-of-the-art demodulators used in inductive communication systems. The proposed demodulator that was designed, fabricated, and tested provides high data rates at an ultra-low power budget and a very small silicon area of 2100 ${\mu }\text{m}^{{2}}$ . More specifically, a data rate of 9.04 Mb/s can be achieved at a cost of only $13.68~{\mu }\text{W}$ power consumption. This represents an energy efficiency of 1.5 pJ/bit, which is 8 times smaller than the best state-of-the-art competitive demodulator.