A low-complexity and high-frequency ASIC transceiver for an ultrasound imaging system

This article presents a high-frequency application-specific integrated circuit (ASIC) transceiver for an ultrasound imaging system designed with a focus on low complexity. To simplify the design, it employs a conventional Class-D power amplifier structure for the transmitter (TX) and a resistive feedback transimpedance amplifier (TIA), which consists of a common-source amplifier followed by a source follower for the receiver (RX). Through careful optimization, the RX achieves a measured transimpedance gain of 90 dBΩ and an input-referred noise of 5.6 pA/√Hz at 30 MHz while maintaining a wide bandwidth of up to 30 MHz for both the TX and RX. The power consumption of the TX and RX is measured to be 7.767 mW and 2.5 mW, respectively. Further acoustic performance, assessed using an annular capacitive micromachined ultrasonic transducer (CMUT), showed a 1.78 kPa peak pressure from a 20 V pulser and confirmed the full bandwidth compatibility of the CMUT's bandwidth. The ASIC transceiver has been fabricated using a 0.18 μm HV bipolar-CMOS-DMOS (BCD) process.