driver for XP-G, LM3424 based?

[link1896]

Hello everyone, this is my first ever post at cpf, love everyones work, this place is amazing.

I'm the Technical Manager for a Cinema supply company, and so I spend a LOT of my time working on complicated/dangerous/expensive machinery in the dark, so I've chewed through a LOT of headlamps. (this also means I have light and color meters from work, Ultra Stereo Labs PSA and PCA. should get some people excited, the PCA can provide spectral graphs.)

I just put an XP-G R5 into a PT Ultra, and 0.89 amps, 3.194 volts just isn't enough. Currently running with NiMh 2500mAh with a 15 minute Varta charger, does me well, but now I'm into my 30's, my eyesight is slowly degrading. Still better then 20/20, but not as good as it once was.

I'm dreaming of the following:
lithium polymer battery pack belt mounted (already got a stack from my RC toys)
four XP-G's
fan cooled copper heatsink for the XP-G's 30x30x8mm 5v fan
and a LM3424 driver (i'm amazed at what National has squeezed into this package)


In the mean time, does anyone know what IC lurks under Princton Tec's black potting mix on the Ultra's board? I'd love to bring it up from ~3.2 volts for now.

 

[vaska]

LM3424 is a nice driver except one thing: 3 mA quiescent current is too high.
Moreover, I don't think that the fan is really useful. I use to work with such a headlamp, using MC-E, and it hardly reaches 60C indoors at 600 lm output. The heatsink is 32 mm in diameter. Keeping in mind, that XP-G is much more effective thus dissipates less power in heat, be sure the temperature will be even lower.
By the way, I'm 52, but I use to work on Mid mode which is 200 lm. Maybe you'd somehow treat your eyes not to loose vision at all