fryed the ld, but why?

[kendon]

so finally i created my first led, my lpc-815 loc would give a fine control light now... :'(

what did i do wrong? only thing i could find in my setup was not isolating the solder joints at the wires between the driver and the ld (i had two wires coming out of the aixiz, two coming out of the driver, and soldered these together). the adjustment of the driver was at ~250ma, which worked fine just minutes before the accident.

is it possible to kill the diode by shortening the circuit over the diode? if yes, why? just for my curiosity, i know it was dumb not to isolate the joints...

 

[Viracocha]

Could be that you didn't discharge the capacitor before attaching the LD. Or maybe there was some current comming from your soldering iron which passed through the LD and grounded into you. Small enough that you didn't notice it but large enough to hurt the LD.

One suggestion i read here a while back was to always wire the pins of the LD together by wrapping a single strand of copper, stripped from some flex, around the pins. This shorts the pins out protecting the LD from soldering iron currents and charged capacitors.

 

[kendon]

i did discharge the cap before soldering the ld.

what you say about the soldering iron sounds reasonable, but i think the iron should be grounded to prevent things like that. but i will measure the iron againts ground to verify that. i don't think this is the reason, b/c it was not the first ld i soldered with that iron, and like i said it _should_ be grounded, b/c it was made for soldering electronic components, and these have the tendency to be esd sensitive. of course that doesn't mean it could be, given the fact that i was using an absolute cheapass soldering iron... :

 

[kendon]

the soldering iron seems to be grounded, any other ideas? i am not crying after the ld, but i'd like to know what happened, to understand it and to prevent it from happening again...