Graham, could you ask your `analog guy' why he needs +/-18V? Normal
linear supplies are +/-15V. It almost sounds like he has 15V regulators
on the analog side. If he can use +/-15V, or better yet, +/-12V, you
have many more options. Ask him if one of the above supplies would
work. If so, I have some ideas that may be of help. Note, I'm
assuming he's working with a common input range of +/-10V.

   As far as the other supplies, as others mentioned; Linear, Maxim,
TI, National, and others have very efficient ICs that will generate
those voltages with a minimum of components. Take a look at some of
their web sites and Switcher CAD porgrams.

   - Tom


------------------------------------------------------------------------
Tom Handley
New Age Communications
Since '75 before "New Age" and no one around here is waiting for UFOs ;-)

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