[sdiy] SSM2164 last time buys

[Joe Grisso]

On Sun, Feb 27, 2011 at 3:16 PM, Andre Majorel <aym-htnys at teaser.fr> wrote:
>
> Last week I was thinking of a way to
> enforce a both-rails-or-neither rule.
>
> Resettable fuses in thermal contact might or might not work. The
> best solution I've found is a DPST 24 V relay, of the normally
> open type, driven by both rails in series. Bad idea ? You tell
> me.
>
> Probably not suitable for protecting individual modules as
> relays draw not insignificant current.

A decent system-wide method would be good if you have a known 5V
supply. You set comparators for both +V and -V rail and feed those
into an AND gate which uses a common line to turn on and off a pair of
MOSFETs in series with the +/-V rails. Only when both +V and -V rails
are stable and happy does the logic circuit turn on the FETs. Of
course you'd need a pair of gate drivers as well to make sure they
clamp on and off, but that's a small price to pay system-wide.

Best,

-- 
Joe Grisso
Detachment 3, Ltd.