Power amplifier for HF and HV output - has push=pull power MOSFETS as output devices driven by symmetrical supply voltages via pre-amplifier circuits

摘要

The power amplifier has a pair of identical MOSFET transistors (1,2) with a driver circuit (11, 12) each and a preamplifying stage (16). Each MOSFET is fed by a symmetrical power supply (5) of 200-1000 V driven by a current of few amperes to a load impedance (10) over a frequency in the range of 100 KHz to 1 MHz. The driver circuit brings the gate-source voltage of the MOSFET transistors to a level of 2-6 V. The pre-amplifier circuit with a feedback divider (17, 18) is coupled to the driver circuits. A current sensing resistor (4) and a regulator circuit (13) ensure that the load current, Il, does not exceed a pre-set value and does not damage the output MOSFET transistors. USE/ADVANTAGE - High electrical performance of amplifier makes it ideal for ultrasonic transducer driving.