-5V power supply

**gizmomkr** · 03-06-2001, 04:16 PM

Annyone have schematics for a small -5V supply using comon parts ( I have a couple, but I want to get the parts from radio hut, not mail order) all mine use regulators that radio hut dosent have

**Arby** · 03-06-2001, 06:45 PM

I order stuff from www.mouser.com and get it in 2-3 days

**AussieGuy** · 03-06-2001, 09:31 PM

Gudday,
Go to maxim's homepage and do a search for the MAX774...-5v at 1 Amp inverting switching regulator. Page 10 of the data sheets has some usable schematics, although some of the parts may be a bit hard to find...but then every power supply I have looked at has had had hard to source parts...
Cheers,
Fab'
p.s also look at www.sproggy for other ideas

[This message has been edited by AussieGuy (edited 03-06-2001).]

**Alives** · 10-10-2001, 03:27 PM

Originally posted by AussieGuy:
<STRONG>Gudday,
Go to maxim's homepage and do a search for the MAX774...-5v at 1 Amp inverting switching regulator. Page 10 of the data sheets has some usable schematics, </STRONG>

Im planning on using this chip for my -5V but page 10 shows 3 schematics. Which one should I use? something about bootstrapping or not. Heres the link to the schematics: http://pdfserv.maxim-ic.com/arpdf/MAX774-MAX776.pdf

thanks in advance.

PS I cant get -5V from my power supply as im using a laptop

**Aaron Cake** · 10-11-2001, 08:05 AM

Moved to Power Supplies.

**Beehphy** · 05-30-2007, 12:50 PM

Originally Posted by Alives

Im planning on using this chip for my -5V but page 10 shows 3 schematics. Which one should I use? something about bootstrapping or not. Heres the link to the schematics: http://pdfserv.maxim-ic.com/arpdf/MAX774-MAX776.pdf

thanks in advance.

PS I cant get -5V from my power supply as im using a laptop

I would suggest non-bootstraped mode. -5V to ~14V is 19V difference and one pin has a 21V limit. thats close. to close for me to feel safe.

I personally use Digikey.com as my parts source. I perfer the parametric search abilities over mouser.

FYI parametric = sorting and filtering by multiple part spec's simultaniously (i.e. voltage, value, package tolerance, etc.)

Also i had problems finding the 774 in qty less than 1000 so you may want to get a sample for free from maxim. just make up some $h!t and they'll send a few to you. its worked many a time for me.

PS. I'm EE so hit me up if you have Q's.