when I put in a green backlight on my DMG I also switched the power LED to a Green one and now it is not very bright at all.
it looks as if it dimming from low battery power.
and yes I tried fresh batteries
what up wit dat?
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KC
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LEDs have different input voltages. You will need to adjust the resistor.
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matt's mind
its the resistor marked R1 on the LCD PCB.
you can google "led resistor calculator", assume the current to be 20mA, the voltage source to be 5V, and it will spit out the resistor to use (depending on the LEDs own specs, which is the unknown variable you'll provide (i can't tell you))
or, google ohm's law and just work out the math the long way. the little browser applet resistor calculators are nice though
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matt's mind
something like this: http://led.linear1.org/1led.wiz
that one is very basic. if you needed to add multiple LEDs for whatever reason or for a mod down the road, and just want to skip the simple math, the google search will give you some more advanced versions.
thats really all there is to it! easy peasy, lemon squeezy
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KC
ok well I used Nonfinites diffused power led and he doesn't have that info listed so then how do I know the diode forward voltage?
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matt's mind
just use the default ratings in the pop-up box they give you (the question mark)
i notice there are two greens in the pop-up though. use 2.2 as the value first, if its not bright enough, use the other rating. i'm betting he's using ones rated for 3.xV, but don't want to tell you that and you burn it out for some reason...
150ohm should work fine, i'm guessing you'll end up with something close to that... but, try out a 200-220ohm one first in case he's using one of the lower voltage rated green types