On-chip reduced wire transceiver for high frequency CMUT imaging system

A system-on-a-chip (SoC) for interfacing with a high frequency capacitive micromachined ultrasound transducer (CMUT) imaging array is presented at the post-layout simulation level. The SoC receives high and low voltage supply and clock from external sources and transfers the RF echo signal directly through a single wire. It occupies a 1.26 mm(2) chip area in a 0.18 mu m high voltage CMOS process and consumes 11.2 mW and 4.5 mW from the 1.8 V and 46 V supplies on the receiver (Rx) and transmitter (Tx) sides, respectively. The Tx generates a unipolar pulse with 12.5 ns width and 44 V swing in each firing. The Rx has a 95 k Omega resistive feedback transimpedance amplifier (TIA) that amplifies the echo signal with 296 mu V noise integrated over 20-50 MHz band. High voltage regulators provide 44 V, 40 V, and 4.5 V supplies for the Tx driving circuits with 98.2%, 6.98%, and 1% efficiencies, respectively.