3.3v regulator

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Offline
Joined: Aug 9 2004
Posts: 5

I've been tinkering with color classic tune ups for a while i finally got my 6500/250 board to work in one.
Except the 3.3v regulator unit i need for the pci cards and the g3 upgrades. Is there any detailed info on making one or to get one?
I'm tired of blowing cash on components and wasting time farting around on this regulator.
It's a basic circuit i even have the specs of the regulator here.
http://www.national.com/ds/LM/LM3940.pdf witch is why it's tweaking me off even more
Is there any help out there?

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Offline
Joined: Aug 9 2004
Posts: 5
pci amps?

I was also wondering what amp level is for the pci function

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Joined: Dec 20 2003
Posts: 180
I think that the 1A which the LM3940 provides. . . .

may be a bit limiting.

As for the circuit for the regulator, we've never published one, because each regulator IC needs different components around it.

However, the .pdf file you referenced showed a typical circuit with two capacitors. There are similar circuit diagrams published for all such ICs.

Just build a circuit like that on a small piece of 'vero-board' or similar - boards with holes at 0.1" intervals, and make the 3 connections to the 5.0v input, 3.3v output and earth on the edge connector, and all should be fine.

Pay attention to any heatsink recommendations with the IC specs.

Stuart

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Stuart Bell,
Developer of the PowerCC site a long time ago.

mobilepet's picture
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Joined: Dec 20 2003
Posts: 27
If you aren't sure about a he

If you aren't sure about a heatsink, use something generally the size of a matchbook, but larger is ok too. Stop me if you know this.. And make sure to use some kind of heatsink paste / insulator with the heatsink.. Good work to you. -mobilepet

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