Gamecube LED replacement, you should replace the resistor too

I also put this topic in some other forum, in case you might find this text somewhere else don't be surprised

Replacing the LED of the Gamecube is one of the most common mods. All you have to do is solder the old LED out and solder the new one back in. Although this does work, it isn't the way to make you new LED shine as bright as they are supposed to.

I did some testing and measuring when using a blue LED. I found out that just replacing the LED caused the new blue LED to run only at a current of 6mA. In general, LED's have their optimal life-expectancy/brightness ratio at about 20mA.

In order to make you LED run at a higher current, you need to replace the resistor that is positioned right next to the LED. The stock resistor has a value of 330ohms (at least mine had). The voltage over the resistor+LED is 5V. All you need to know more is the forward voltage of the LED you want to use. This is stated in its datasheet. I.e. blue LED's generally have a forward voltage of 3.2V.

Now look for a LED calculator on google, like this:
http://linear1.org/ckts/led.php

Fill in:
the supply voltage, which is 5V
forward voltage, 3,2V for most blue LED's
current, 20mA for most LED's
(some of this info is given on that site as well)

Now click 'find R' and the needed resistance value is given. Since 90 ohm resistors don't exist, you need to find the one closest to that, which is 100ohm, which will make a blue LED run at 18mA, which is good

Well I wish you brighter days

hm.. yes i was wondering why my green LEDs of 3000 mcd are sooo much brighter than blue LEDs of 2000 mcd under the same voltage and resistance on my bread board...

What is the value of the resister that comes with the GC?

Will refusing to change the resister cause the LED to die a lot faster?

ok, first, the original resistor i believe is 330 ohms. second, i think it would kill your led faster. third, I posted a link to that site too . Only my link is better. . http://led.linear1.org/led.wiz that is a wizard that will design an array with multiple leds. It'll design it in parallel or series, depending on which would work best. Nice info, I'll look into that when i change my power led. Thanks!

If you'd use a 100 ohm resistor your blue led would run at 18mA. Sure it may not live as long as on 6mA, but yet again you're talking about many years... LED's are ment to be used at about 20mA

The original resistor is 330 ohm, is stated that already in the first post

Hi,

Simple question with the Voltage drop across LED, where does this Forward Voltage terminate?

Just being safe...

Thanks,
DuckmanX

Update: Nevermind... did some testing, got it working, nothing destroyed...

Let the forum necromancy commence...

Okay, so anyone who knows about this, I got some new LEDs, and I'm wondering what sort of resistor I need.

Any advice would be appreciated.