5 Mar
2005
5 Mar
'05
10:32 p.m.
On Sat, 05 Mar 2005 20:57:48 -0800, Eric F. <elf at ucsd.edu> wrote:
9000 VAX wrote:
I guess the computer is pure CMOS, no TTL and that's the reason why it
is designed to use the expensive Lithium battery. If so, I would guess
that it can work with 4.8V (3.6V +1.2V), or 5.1V(3.6V+1.5V) too. There
are cheap 3.6V Lithium AA size batteries. What you need to do is to
add a 1.2V or 1.5V battery, and that is easy.
I have just bought two from goldmine-elec. I measured one and it had
3.70V open voltage. (You need to cut the leads though; It is a SAFT
brand!)
http://www.goldmine-elec-products.com/prodinfo.asp?number=G14788
vax, 9000
I guess the lab computer uses 5v CMOS devices and
the
2x2.5V battery let them skip the voltage regulator.
That does have rhyme & reason to it -- yes.
(And you are correct in that it takes 2 of these 2.5V lithium cells -- I
failed to mention that in my original post.)
I suppose it just couldn't have been foreseen by them that SAFT would
discontinue manufacturing this particular battery at some point down the road.
Still, though, wouldn't manufacturing a device which relies on a sole
provider for its power cells raise a flag or two during the design process?
It is not like these batteries are as common as dirt -- like your typical
Duracell "AA". (Then again, I'm no hardware engineer, so I'm not
familiar
with how these decisions are made.)