A 48μW Analog Front End Circuit Design for an Ultrasonic Receiver 0.18μm CMOS

Ultrasonic transducer based sensor systems are widely used in wearable biomedical applications for indoor location sensing, tracking and other zonal compliance purposes. A system used for zonal compliance typically made up with a zonal transceiver device and a battery powered wearable device with the associated control logic at each interface. Being battery powered, the design of analog interface circuit to the wearable device is significant to overall performance of the system. In this paper, we present a fully integrated Analog Front End (AFE) interface circuit for the ultrasonic receiver designed and fabricated in 0.18μm CMOS. Measurement results shows that the single chip receiver operating at a centre frequency of 40 KHz reduce the power consumption to less than half over the discrete version.