help with led mod

[gamerdude767]

hey,


     i wired up a 0603 led to ground and 3.3v on the 360 motherboard but after like 20 seconds the led would burn-out.. ive looked at the info that came with them and it said
Forward Voltage (mA): 3.0-3.6  so would i need a resistor .. would a 30ohm be good enough ??


 thanks in advance
scott

[taylorclark]

yes, 30 ohms should work. for future reference: http://ledcalc.com/?vs=5&vl=4.5&cu=30&ledcount=2&type=parallel&r=&m=&validwt=&validvirta=&validledvirta=&validledw=&validw=

[gamerdude767]

okie dokie .. thanks for quick reply, ill be ordering some tonight

[psp339]

Why not wire them to the 5v source? I wired 22 to the 5v standby with 8.2ohm resistors and its hooked up my pulse vu 2x. 

[HYOSC1NE]

yeah u need a charge resisitor V=iR since ur conecting to a 3.3 voltage and the disire current is 3mA a 1k resistor would do fine but might not so bright, so a 330 Ohm resistor is wat i would recomend