16 Aug
2006
16 Aug
'06
4:23 a.m.
Subject: Re: PDP-8 /e/f/m memory
From: Don <THX1138 at dakotacom.net>
Date: Tue, 15 Aug 2006 09:33:25 -0700
To: General Discussion: On-Topic and Off-Topic Posts <cctalk at
classiccmp.org>
While your wailing about your maglites your also talking about that
mere 7 year shelf life.
Because most batteries have shelf life! The
average battery dies in
a few years from just sitting. The LI cells are designed for very long life.
I have a few sub-C sized LI cells that are over 15 years old and going strong.
The shelf life (self discharge rate) of most batteries is *MANY*
YEARS. The AAA cells I bought last year for my Visor have a
"expiration date" of 2013. A low power BBRAM design essentially falls below this
self
discharge rate (unless you get sloppy with the design).
The real problem is ensuring that the batteries (i.e. the
equipment that they are stored in) doesn't sit in
temperature extremes, high humidity, etc.
Yes, I know this from my first CMOS design back in the late 70s.
Heat is a big factor even for the leakage current of the CMOS.
And, if you're storing your '8 in those
conditions, I suspect
one of these days you'll be in for an unhappy surprise as
you "suddenly" discover components that have fatigued
What has this to to do with the topic at hand?
Allison