Uploaded February 2023 | Updated September 2026, 3 weeks ago
This is the second part of an experiment to build a high voltage switch using Silicon carbide MOSFETs forming a high voltage switch. The switch has to be capable of pulsing a magnetron supply at high speeds. Silicon Carbide MOSFETs have low 'on' resistance and have breakdown voltages above 1kV making them suitable. Here we are adding them in series to obtain a breakdown voltage of around 6kV, well above the failure point for a single device.
This is still quite a tough ask, as pulses create transients and spike which can be momentary but fatal for semiconductors. The magnetron used is a generic oven type and not designed for pulsing. They can be operated slightly above their ratings but cease to produce any output much below, where they just behave as resistive diodes. Electrically they present themselves as a complicated load resistance with avalanche behaviour depending their supply voltage.
CONTENT:
00:00 - Intro
00:10 - 2nd attempt
01:00 - 3rd design
02:55 - test 1
03:30 - test 2
04:52 - layout
05:53 - last test
This is the second part of an experiment to build a high voltage switch using Silicon carbide MOSFETs forming a high voltage switch. The switch has to be capable of pulsing a magnetron supply at high speeds. Silicon Carbide MOSFETs have low 'on' resistance and have breakdown voltages above 1kV making them suitable. Here we are adding them in series to obtain a breakdown voltage of around 6kV, well above the failure point for a single device.
This is still quite a tough ask, as pulses create transients and spike which can be momentary but fatal for semiconductors. The magnetron used is a generic oven type and not designed for pulsing. They can be operated slightly above their ratings but cease to produce any output much below, where they just behave as resistive diodes. Electrically they present themselves as a complicated load resistance with avalanche behaviour depending their supply voltage.
CONTENT:
00:00 - Intro
00:10 - 2nd attempt
01:00 - 3rd design
02:55 - test 1
03:30 - test 2
04:52 - layout
05:53 - last test
