Wideband portable power amplifier design for very high frequency ultrasonic transducer applications

This paper describes the design of Class A wideband power amplifier (PA) for very high frequency ultrasonic transducer applications with power field-effect transistor (FET). The PA is a one-stage common-source amplifier with 28 V supply voltage. The measured gain of the PA is 15.8 ~ 17.8 dB in the range of 100 to 250 MHz and current consumption of the PA is 0.3 ~ 0.4 A. The measured 3rd-order input and output inter-modulation points (IIP3 and OIP3) of the PA are 12.25 dBm and 27.25 dBm, respectively and the measured noise figure of the PA is 2.14~2.98 dB in the range of 80~120MHz.