[sdiy] can a PSU destroy voices chips?

[Neil Johnson]

Hi,

Robyn Mayol <rominbayol at gmail.com> wrote:
> Would anyone be able to explain how this failure in the positive supply results in the death of those IC's?
>
> Please :)

At a guess I would think it similar in principle to the mechanism that
causes SSM2164s to die if the negative rail disappears.

Although I don't know the exact reason for the 2164 death mode (and
Analog Devices declined to comment), I suspect that some internal
substrate or junction that is normally biased to a safe non-conducting
state ends up very much conducting a lot of current, getting hot, and
burning.  The fix for the SSM2164 ensures the negative pin is held at
a voltage below which a normal PN junction will turn on, so keeps it
safe.

I have no idea what would be needed to keep a CEM3340 safe -- several
2164s were burned during experiments to resolve this issue.  Anyone
care to donate a tube of CEM3340s so we can experiment?  Some may
burn.....

Neil
--
http://www.njohnson.co.uk