LM3886 power amp Power Supply

[Michael Allen]

I've seen a couple guys using transformers to supply power to these LM3886 amps. Do I need a transformer or can I use a MAX1044 to supply the +/- 18V.

[R.G.]

You may absolutely use a MAX1044 to supply the chip - as long as you want less than about half a watt of undistorted output, maybe less. I'd have to do the numbers.

There's a crucially important concept lurking under here.

You can't get more power out of an amplifer - chip, discrete, or tube - than the power supply can make. In fact, you can never even get 100% of what the power supply can make, as some of it is inevitably wasted.

A MAX1044 or other charge pump can only provide a relatively tiny amount of power compared to the amount that's needed to move a speaker. If you actually want to drive anything with that LM3886, yes, you need much more power than a charge pump chip can provide. That can be a transformer power supply, car batteries, D cells in series/parallel, dynamos, etc. But the conventional wisdom is an AC line transformer/rectifier/filters.

[Michael Allen]

Ok so it deals with Power, not simply voltage....