Hello guys,
I am a big fan of seeing the reaction of a person coming in contact with 300V, seeing few hundred Joules capacitor discharge in 100us so I build this simple FlyBack converter to play with.
The FlyBack converter consist of a Mosfet switch driven directly by a pic controller with a On time relative to VCC. The Mosfet rise time is not too bad, in the 40ns range. A resistor feedback divider coupled with the PIC’s comparator to detect if desired output voltage is reached before every switching cycle. The output ground is not isolate.
There are some upgrades in the works because some users would like a clean output for vacuum tube audio and photo multiplier application. These are drive the converter in resonant mode by detecting zero crossing with the comparator in order to compensate for the ~pour couplings factor of the transformer causing noise and an optional output filter. Also a potentiometer adjustable output voltage from ~0-1250V. And controllable output voltage with an RC type PWM signal. (can you imagine a RC receiver with the power supply and a battery HAHAHAHAHA) Upgrading the PIC12F to something with more pins to accommodate the extra features.