Recently i've been tinkering with the interrupter of my solid state tesla coil and the circuit that utilizes two ne555 timer ic,one in astable mode and another one modulating via pin 5 of the first ic giving a nice tone with burst like effect.now thats out of the way,upon measuring the duty cycle i've found out that the pusle width is at 50% so here is my question is there any circuit that i can use the vary the duty cycle without changing the frequency, because at 50% duty cycle the mosfets do get quite hot after some time.It draws close to 5 amps at 240vac input So my idea is to use an comparator for example the LM311 to set the duty cycle to a certain value.for further information feel free to ask in the comment i will reply soon as possible,thank you.
1 Answer
I've done this sort of thing many times in the past using the old MC34060 chip. Look up the data sheet, there are some example circuits in there.