Design of a high-voltage analog front-end circuit for integration with CMUT arrays

Capacitive Micro-machined Ultrasound Transducer (CMUT) technology is becoming popular in ultrasound imaging due to its many advantages as compared to its piezoelectric counterpart. These advantages include ease of fabrication and integration with CMOS readout circuitry. This paper presents the design of a high voltage (HV) transmitting driver and a low-power variable-gain receiving amplifier which are intended for integration with CMUT arrays. Also, by Verilog-AMS behavioral modeling of the CMUTs, their loading effect is modeled more realistically. The circuit is designed in a 0.8-μm HV CMOS technology. The transmitter is capable of generating pulses of up to 300 V. The gain of the receiving amplifier varies from 72 dB to 90 dB while its bandwidth ranges from 11 MHz to 9 MHz. The amplifier consumes 3 mW from a 5V supply and has an input resistance of 1KΩ.