Abstract:
To meet the requirements of tumor ablation, a solid-state single linear transformer driver (LTD) module has been developed based on push-pull circuit. The single LTD module has four push-pull branches on its primary side and a short-circuit branch with RCD snubber, and it can output bipolar rectangular pulses with short rise time and with pulse width ranging from hundreds of nanoseconds to several microseconds. FPGA is used to generate the signals to drive the MOSFET switches, which are isolated by photoelectric conversion. The single LTD module is tested. The experimental results show the bipolar rectangular pulse is achieved successfully, and the repetitive frequency is up to 0.5 kHz. The pulse width can be adjusted flexibly from 300 ns to1 000 ns under 500 V, and the rise time is about 13 ns. When the pulse width is achieved from 1 μs to 8 μs under 250 V, the maximum flat top drop of waveform is less than 5% and the magnitude of back edge overshoot is about 15%. At the same time, by adding the LTD module one by one, higher voltage can be easily realized.