Jim Thompson wrote:

On Sat, 28 Jul 2007 16:28:47 GMT, Joerg
wrote:


Jim Thompson wrote:


On Fri, 27 Jul 2007 23:31:27 GMT, Joerg
wrote:



John Larkin wrote:


[snip]


It depends on the crimped seals, which is a matter of luck. My other
problem with alums is that I want my gear to work to at least -20C,
perferably -40, and elec esr's skyrocket below 0C, so my switchers
will go crazy or at least make huge amounts of ripple.


Yes, that's a problem, one that is often overlooked in automotive. For
hi-rel stuff with temperature extremes I try to limit myself to
ceramics. It's amazing that you can get 10uF for pennies nowadays.


"Overlooked in automotive"? What amateurs are you talking about? All
my automotive stuff was designed around -40°C to +140°C.


Well, yes, AFAIR you worked for Bosch. They make the good stuff. But my
wife once had an "all electronic" car in Germany and then one night they
had a hard freeze. -20C or so. The whole thing went into hibernation,
even the dashboard didn't work anymore. There was battery juice. She
called the shop, they sent out the truck and brought the car into their
"thawing warehouse". After forking over some Deutschmarks it worked again.


Even the US stuff was specified at -40°C to +140°C.


Haven't checked US vehicles lately. However, "specified" and "actually
performing" are often not the same thing.


Mercedes products are hilariously noted around here for "melting"
dashboard electronics ;-)


Here they hold up pretty good. For me they are too electronic though, I
prefer vehicles that are simpler.

--
Regards, Joerg

http://www.analogconsultants.com