breathing life into old chips

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Fri Apr 4 18:39:25 2003

> hi,
>
> this is sort of off-topic as it applies to my TV and not a computer, but I bet
> some of the folks here can offer advice... :)
>
> the microcontroller in the set seems to have developed a fault which only
> appears when the set's warm. Tracking down a replacement seems to be easier

Possible. I assume you've checked for dry joints, that the IC's power
supply is good (check decoupling caps too), that the reset line is right,
and that the crystal is good (a suprising number of crystals fail in TVs...)

> said than done as the chip was obviously discontinued a while back (and then
> I'd have to worry about the on-board ROM anyway).

Have you tried a TV spares place? You might still be able to get the
original part, correctly programmed.

>
> At the moment though there's no heatsink on the chip - if I do stick a heatsink
> on it in the hope that it keeps it cool enough to operate, is it still likely
> to fail at a later date anyway? Once a chip's started to exhibit heat-related

In my experience it will get worse :-(

-tony
Received on Fri Apr 04 2003 - 18:39:25 BST