Hello all,
I'm putting together a sound activated trigger for a friends camera, it uses
modulated IR (38-40 khz, like a remote control) and since this was meant for
outdoors use, and possibly for use with rifle and having to deal with muzzle
flash, and having to beat that out, I decided it might be worth it to try a
3W IR LED from deal extreme. It takes 1.5A @2v. Now for driving that, could
I get away with using a 2A peak mosfet gate driver?  I was going to put a
28ish uF capacitor in series to keep from damaging anything if it got stuck
on, and a diode in anti-parallel with the LED to discharge the dc block cap
on the off cycle.

The IR code for the shutter release works out to a 4% ratio of modulated
time to off time, and I'd only send the code once or twice giving it a 100
or 200 mS duration respectively.  Am I just working against average thermal
dissipation here, and not overheating the driver in the long run? or will
localized heating on the be an issue due to the prolonged pulse duration?
Anyone else use and abuse these in a somewhat similar manner?

Its a shame the D50 didnt come with a wired shutter release, just an IR
reciever, it's plenty capable otherwise, but the 100mS delay with the remote
(could be less, hopefully, there is 37 mS of pulses and then a 63 mS dead
time before the next pusle, ) makes it harder to catch fast events.  We'll
still be able to catch people mid recoil however though, just not the action
cycling if its a 100mS delay.

Thanks all,
-- 
Jonathan Hallameyer
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