Sorry I'll clarify a little.  :)

I'm assuming AC mains in, so I need a step-down, etc yes.
I don't need variable but I also will be using 12V, -12V .1A regs on it
as well, so I prefer the 18V, -18V transformer Chris suggested.
I would prefer to keep noise down to <5 mV.
Load is varying anything from 3ma to 3A.
Efficiency isn't really important but I'd like to get away with smaller
heat sinks, but oh well if not.  :)

I don't mind describing the application but I wanted to keep the post
as short as possible.

Could I use a hexfet as a pass-transistor so it won't get as hot or is
this a bad idea for some reason?

Thanks,
Aaron

>There are a zillion ways of doing this (most very similar)
>Useful info would include:
>
>- Variable or fixed.
>- If variable, tracking or independent.
>- Do you have existing input supply or transformer etc? If so what?
>- What is the load?
>- Noise important.
>- Efficiency important?
>
>The better people understand your need the more likely it is that they
>can
>help

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