Re: Very unusual. Light causes circut to connect??????!!!!

That's what I thought to start with to start with also. But I found that it
could be activated with an IR diode. I have isolated the spot. It is a
testpoint that leads to a chip on the other side. The testpoint is a small
hole.

I don't know what or why it works, but I wired an IR diode in and volia. The
button is functioning how it should, except you can't do a master reset with
it.

My theory on why it is working is that there is a crack in the chip on the
other side. But since I know nothing about how chips work I don't know if
that is a possible cause.

- Mike

"Not me" <nobody@xxxxxxxxxxxx> wrote in message
news:ff20d11c8s4apah7rapo8nmqv7e0fh4kfb@xxxxxxxxxx
> On Fri, 8 Jul 2005 02:19:48 -0400, "Michael Kennedy"
> <Mikek400@xxxxxxxxxxxxxx> wrote:
>
>>Hi, I bought an ipod with a broken menu button. Well i thoght I'd just
>>have
>>to resolder or buy a new switch.. I resoldered the switch with no luck and
>>then I checked it with an ohm meter and it checked good. Now here is the
>>Weird part, I was inspecting the board under my desk lamp with it powered
>>on
>>and the switch started working, well sort of.
>>
>>If you shine light on part of the board it closes the circut like you
>>pushed
>>the button down!!!??? There is not an optical sensor that i can see
>>anywhere near there, and it is away from the switch that doesn't work. It
>>has some smt resistors in the area and some holes that appear to go all
>>the
>>way through to a chip on the other side.
>>
>>So my question is what the heck is going on??? I've never seen anything
>>like
>>this before. It is not supposed to be light activated..
>>
>>I'll put some picures up on my web server when I find my digital camera
>>charger.
>>
>>- Mike
>>
>
> How close are you getting with the light? Could you be causing some
> sort of thermal effect?


.

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