Anyone expericned with iphone light mods?

[algar32]

http://www.adafruit.com/blog/2012/10/18 ... our-apple/

I have seen this mod all over the place and would like to attempt it myself. I have a few questions first...
When I first researched this I learned that the mod damages the screen over time. Has this issue been fixed by anyone selling the mod? Is there anywhere else to get power from other than the lcd power rail?

If it hasn't here is what I am planning to attempt:
- someway that senses voltage through the lcd rail (so it knows when to light up), but is powered by a small watch battery or whatever battery I can manage to cram into the back of the iphone (I realize it is a tight fit and this will be a challenge). The watch battery will last for a short amount of time, but will obviously have to be replaced unless there is a way to put a separate rechargeable battery in there and wire it as so.

This should allow the screen to light up without damaging the lcd.

Any suggestions/advice/insight?

Thanks.

[semicolo]

I don't think the lcd will be damaged just because you're stealing a bit of power from it, does anyone have any justification for this?

[Osgeld]

not me, every LCD I have taken apart has had the backlight with its own power source, which now days drives a string of LED's

[algar32]

There are several articles like this: http://www.imore.com/rethink-installing ... -iphone-4s
(this particular one doesn't seem very credible), but there are enough stories out there saying it dims/damages the lcd over time. I find this hard to believe, but I was hoping I could to get your opinions on it. I really want to know from an electronics standpoint if the tiny amount of power from an led would be enough to damage the phone. Thanks for your answers thus far.

[Osgeld]

the only thing I can think of is that the LED has no regulation?

I cant comment on the iphone design, I would think that they are using a constant current source, so no matter what you drop on it, it will provide its set current, but I have opened LCD's where its a bit of flex pcb with LED's and resistors in line.

That could cause problems if there are no limits on the mod's LED, running full blast open and hoping something in the circuit keeps it from popping will degrade the LED quickly over time (and they degrade over time even when properly powered). Putting more stress on the power giver causing it to perform poor, then maybe your screen gets dimmer cause it takes more oomph to drive a small string of LED's over a single one.