Hello,
I'm considering using a simple P-P converter for a power supply project.
Vin: 12VDC Regulated, up to 1A.
Vout 1: 300VDC, 10mA.
Vout 2: +/- 15VDC, 50mA.
Since the input voltage source is already regulated, I don't think I need flyback regulation.
I've made some progress using the UCC28089, but I could use some help optimizing it in the following ways:
1) Suggested mosfet and coupling resistor value.
2) The high voltage secondary feeds a voltage doubler. Please suggest any HF filtering that may be required and advise adequate filter capacitor value.
3) I was considering using standard 3-pin linear regulators on the bi-polar 15 supply, mainly for filtering out noise. Is that overkill and is there a cleaner/simpler suggestion? I have additional board space and room in the budget as long as it doesn't get too out of hand.
I've had a preliminary transformer made with a primary DCR of about 0.4 ohms. Right now I'm getting +/-18VDC (before the regulators) and about 280VDC no load,
Current draw from the supply source is around 90mA. As soon as I start loading the supply, roughly 30-mA on the bipolar side, the output voltage drops to +/-10VDC even though the input draw goes up to around 150-200mA. That also pulls down the HV secondary supply voltage around 30VDC, so I think my problem is on the drive side.
Thanks,
Steve