+/- 18 volt DC power supply ?

[kringle77]

Where can I get a 120 vac to +/-18 vdc or +/-15 vdc power supply to use on opamp projects? I have found some schematics on line but can't seem to find the proper transformer. Does anyone just make the finished product?

[Toasted]

You're better off adding a portion to the circuit with a MAX1044 to create the +/- 18V DC

[niftydog]

If you're just experimenting on the bench then there are many dual output bench supplies that will do this.

Otherwise you'll need to look at pre-built switch mode power supply modules intended for OEM use.

I don't think you'll find a dual output wall wart if that's what you're after.

[kringle77]

It's looking like I will have to make one from scratch. I'll need:

- two IC voltage regulators +18vdc & -18vdc
-a fullwave rectifier
-2 caps
- 120 vac to 24 vdc transformer
- 2 heat sinks for the IC's
- fuse and holder
- cord and socket

[niftydog]

±18V is an odd one, but ±15V is easy to come by if you know where to look.

Obligatory warning: anyone playing with mains voltages should be competent and follow appropriate safety precautions. There are lethal voltages present and you don't get a second chance!

[Trevorus]

Check www.Mouser.com. They have dang near everything.

[kringle77]

Niftydog, that looks right. I can't tell if it's center tapped though. I think that I need the center tap to ground my projects. Looks good though.
Thanks

[kringle77]

This may be what Im looking for.

TML 05215 5W Miniature Encapsulated Power Supply

[niftydog]

Originally Posted by kringle77

I can't tell if it's center tapped though.

Ground is common to both supply rails.

Originally Posted by kringle77

TML 05215 5W Miniature Encapsulated Power Supply

Looks good too, fairly similar. Trouble with those is they're intended for mounting on a PCB so connecting wires is a bit of a pain. The one I mentioned has connectors on it, but that means you've also gotta get the connectors so...