[PSUBS-MAILIST] LED Light 10,000 Lumens

[Ken Martindale via Personal_Submersibles]

If you go to the forums you can find the latest installment of the LED
driver schematics and parts list.

I found a few errors which I corrected and I changed the PWM IC to one I
have more confidence in.

I did not use a reverse polarity protect diode since I didn't want to throw
away the power in a diode so I used a FET as the reverse polarity protect
device. It cost about $0.80 more to do this.

The cost of the electrical parts is about $88 from Digikey including the
Varo 29 LED array. This is for a single unit and the parts cost goes down if
higher quantity. This does not include the PWB.

I have ordered the first kit of parts from Digikey today to help me in
laying out the PWB which is next. These parts will be used in the first
prototype. I should have an area study done by next week so we can start
firming up the mechanical packing and making it fit into the housing Cliff
has generated.

The design meets all but one of our original requirements as stated in the
spec we generated. Meeting the full EMI requirements of MIL-STD-461 would
require a large EMI Filter which in the interests of small size was modified
to accept a small EMI Filter, mostly common mode filtering. I think it will 

have no problems in the Sub's electrical environment.

One of the things I'm interested in is to put the driver on a single
rectangular PWB so we could use the driver as a stand-alone driver internal
to the Sub so the LED array could be all that is packaged outside the

sub. It would require a 4 conductor cable to the LED array outside the sub.
That may be for the future, for now we are going with Cliff's housing. 

Wish us luck,

Ken Martindale