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Old December 11th 03, 07:51 PM
John Walton
 
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Use a switching regulator -- you can even get an LM317 to "oscillate" by
putting an RC network in the feedback network -- and use it as a buck
converter -- the schematic is on the Nat Semi website -- just search under
LM117.

"Tim" letter T letter H @lakeoriongroup.com wrote in message
...
Went with a KA3406 DC/DC converter pulled off an old motherboard, seems to
be working fine, had to play with the charge caps a bit to get what I

wanted
but lost the heat for sure!

Thanks

Tim

"Tim" letter T letter H @lakeoriongroup.com wrote in message
...
Not sure why this one is elluding me, but , I have a graphics display

with
an led backlight drawing about 450ma @ 5v. While a large 7805 is rated

for
an amp it's getting pretty hot even with a nice sized heat sink.

Any thoughts on another way to drive this backlight? I was thinking of
running it at 12v (it's going in a radio) and a dropping resistor. What

say?

ddz