There is a power supply at Electronc-Goldmine that would work well for
this type of application. It is a Vicor VI-LU0-EU FlatPAC which ouputs 40A at 5V.
The output is trimable to 0.5V. You could adjust the output to 3.3V or to 4V if you
use higher Vf LEDs. The price is $40. 1MHz switcher. Very compact.
The usual caveats about purchasing surplus apply.
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