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IndustrialAction
03-06-2011, 10:29 PM
I need a quick check-up on the resistors I'm planning on using in my build. These are all based on calculations from HERE (http://led.linear1.org/1led.wiz).

AV Switch (blue ring LED)[kill-switch removed indicator]: 1ohm 1/8w (3.3v source, 3.3v [forward], 20mA [forward])

Cyan LED [accent light 1]: 1ohm 1/8w (3.3v source, 3.3v [forward], 20mA [forward])

Green Indicator [accent light 2]: 47ohm 1/8w (3.3v source, 2.2v [forward], 25mA[forward])

Luxeon Rebel Star: No resistor

If you see anything wrong with these, please let me know.

Azmaria Dei
03-07-2011, 01:12 AM
if your feed voltage matches your forward voltage, you really don't need a resistor. i would just leave out the 1 ohm resistors. finding them in 1/8 or 1/4 watt sizes will be hard anyway. the one for the green looks good though.

cannibal869
03-07-2011, 02:28 AM
if your feed voltage matches your forward voltage, you really don't need a resistor. i would just leave out the 1 ohm resistors. finding them in 1/8 or 1/4 watt sizes will be hard anyway. the one for the green looks good though.

Agreed... to Azmaria listen you should

IndustrialAction
03-07-2011, 05:28 AM
Thanks! I actually did find the resistors for about $.09/ea. They're so cheap ordered them anyway but I may skip adding them to the build now. I appreciate the help!

Darth Xusia
03-07-2011, 08:06 AM
So I guess Erv is silly for saying to always use a resistor then? I thought he would know better than anybody.
I would use the 1ohm resistors just to be on the safe side.

Azmaria Dei
03-07-2011, 11:41 AM
when he said to always use a resistor, accent LEDs didn't get into the 3V range. now that there are LEDs that are perfectly matched for his designs, there's no real problem. though if you want to put a resistor in there anyway, go for it.