8*1W Ls at 350 mA or 4 @ at 700 mA on 1 Powerpuck

The LEDdynamics Powerpuck is specced to take an input voltage of between 8V and 15V and generate a constant current output of 700 mA by stepping voltage edit (down to -- Good catch Georges 80), but not beyond, the input voltage.

John at LEDdynamics today confirmed that the Powerpuck circuit is capable driving 8 @ Vf voltage bin H 1 watters at at 350 mA with an input voltage of 13 V to 15 v. This would be 4 * serial by 2 parallel.

Similarly,as CPF'ers have shown that a 1 watt LS can take 700 mA if well heat sunk, the PowerPuck could also overdrive 4 1 watt LS at 700 mA.

If I'm able to score a number of the cheap RxH's being sold through Elektrolumens, I'll fashion a compact hand held lantern with a large array.

For those who don't feel like putting 14.4 V NiMH battery packs together, a cheaper SLA battery can be used with a Powerpuck to drive 3 @ 1 W LS's at 700 mA or 6 at 350 mA.

This seems like a far more cost effective way to control LS current than using a pair of BB400's to drive just one 5W LS.

More safe LS Lumens per buck through this approach IMHO.

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lemlux said:
The LEDdynamics Powerpuck is specced to take an input voltage of between 8V and 15V and generate a constant current output of 700 mA by stepping voltage up to, but not beyond, the input voltage.

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Are you sure it's stepping up? I think you mean step down. If you have 15V input and are driving a single 5W luxeon - then you want to step it down to around 7V - or whatever the Vf is for 700mA of constant current drive.

My 5W driver works the same way - though it will run from 4V to 30V and deliver 700mA constant current. Of course for a Vf of 7V it would need about 8V input voltage to provide CC 700mA. If size is a consideration, mine is not 'potted' but is on a 1" x 7/8" PCB.

george.

georges80

Good catch, my fingers and my mind sometimes go in different directions. Your circuit size is nice.

I anticipate placing one powerpuck inside the body of a headlamp that is powered from external power supplies connected by female input jack. The large size will fit in this body.

HotBeam is installing 3 @ R2H's in separate aluminum heads for me. These heads came from what were originally 6 * Nichia heads on 3AA aluminum lights. He will wire all three of these in serial. I'll use various belt packs providing >10V input to drive this headlamp.