A PMUT Transceiver Front-End with 100-V TX Driver and Low-Noise Voltage Amplifier in BCD-SOI Technology

This paper presents an analog transceiver for PMUT-based portable ultrasound medical imaging probes, working in the 2–4 MHz frequency range. The transceiver, fabricated in a 160-nm BCD-SOI technology, delivers a three-level train of pulses with amplitude up to ±50 V to the ultrasound transducer and collects the back-scattered echoes with a receiver chain, consisting of a low-noise voltage amplifier with programmable gain and a buffer. The circuit, connected to a PMUT, achieves a RX sensitivity of 50 mV/kPa at minimum gain and an input-referred noise spectral density of $13\,\text{nV}/\sqrt{Hz}$ at 2.3 MHz, consuming 5.4 mW. The peak RX sensitivity, obtained with acoustic measurements in a water tank, is 50 mV/kPa at 2.3 MHz.