I'm designing an audio DSP and DAC board, and in the analog section, I'm using opamps that take in differential audio signal and turn it into single ended output. Because the signals are AC, they obviously swing below zero, so I will need a plus/minus power supply. Keep in mind, I'm a software guy, and I'm only doing this as a hobby -- not a pro hardware designer.
I've been researching the internet for about a week, looking for solutions. So far, I've found:
Charge pumps: These are awesome if it wasn't for the fact that they only supply maximum of 100mA. Driving 16 audio opamps will need more current than that.
Buck/Boost inverter These suck. They require complex circuitry and can barely supply higher current output than the charge pumps. To me, this is the big and ugly solution.
Cuk topology I don't have enough background in power electronics to fully understand the mechanisms for this one, but it still requires several inductors and some mess of external circuitry. They are also limited in their current output for the most part.
Power modules This would be a plug-and-chug solution, but it takes the fun out of DIY, not to mention they are quite huge and take up lots of board space.
I've seen some configurations where there is a sort of "half-rectifier" diodes arrangement used for generating negative supply, but I don't understand it.
If someone with enough electronics background can explain to me an easy to implement and understand solution to generating a negative voltage supply, it would be fantastic. Here are my constrains:
- My input voltage is 12V.
- I want my output voltage to be between -12 to -15v (any value there will do)
- I want 1 A current output.
- I want minimal external components. A few is okay, max one inductor.
- Don't care about ripple, noise, isolation, temperature characteristics, or anything else.