Could anyone help me with creating a PWM controller?
I would like to create a PWM controller that has three pot's:
- Duty-cycle pot
- A pot for adjusting the frequency
- a pot for adjusting the output voltage.
I'd also like to create this one just with transistors (so no timer IC's).
I have some MOSFET's that I can use for switching on and off the load.
The PWM controller should output an AC voltage, but if that is too hard to make, an alternating DC voltage is also good.
The frequency range should go from 30-50Hz up to 4-6kHz. (I don't really know if this is going to be possible to adjust with just one POT, but I can also use a Trim pot for this).
You don't need to explain every little detail. I have basic electronics knowledge. I just don't know where to start.
This is what I have until now. It's not working very well because when I change the duty-cycle the frequency also changes.
The frequency POT is also not good because the frequency decreases when I go to higher resistance, and when I'm going to the highest resistance, the frequency increases again :(