676 / 2022-03-31 14:08:50

A high-voltage ultra-short pulse generator sharpened by an avalanche of transistors at the sub-nanosecond edge

avalanche transistors; Marx circuit; ultra-short pulse；pulse superposition

Purpose/Aim

The ultra-short and strong electric fields can produce nanosecond electroporation of the cell membrane, which induces cell self-repair and autophagy. Abnormal autophagy is associated with various pathological processes such as tumor and neurological diseases. 

Experimental/Modeling methods

In order to study the high voltage short pulse in autophagy, an avalanche triode Marx circuit is firstly used to generate a single low voltage nanosecond short pulse. Due to the internal resistance of the avalanche triode during the conduction process, the increase of the Marx series shows the characteristic of output saturation. To further enhance the output voltage amplitude, each Marx is stacked with short pulses from the transmission line transformer to achieve an output of high voltage amplitude. Finally, an all-solid ultra-short electric pulse prototype with a fast leading edge and pulse width of several nanoseconds is developed.

Results/discussion

The experimental prototype under 200 Ω load which is miniaturized, compact, and easy to carry has the output pulse parameters of pulse amplitude of 10 kV, the pulse width of 3ns, and rise time of about 600ps.

Conclusions

Through theoretical analysis, simulation, and experimental results, it is proved that the pulse generator can effectively achieve high amplitude output while ensuring narrow pulse width.