20 Apr
2012
20 Apr
'12
12:49 p.m.
Tony Duell wrote:
Why?
My expeirence is that more compelx ICs are noticably less reliable than
simple ones. An IC (of any complexity) is more reliable that making the
same circuit from discrete components or simpler ICs, but that's not the
issue.
I would think the 555 had a much better lifetime than any microcontrolelr
therefore.
The origianl 555 (as opposed to the 7555, etc) is large-ish junciton
bipolar and thus less likely to suffer static damage than a MOS
microcotnroller. It also has a much wider supply votaeg range and is less
likely to be damaged by supply problems.
And of coruse if a microcontroller fails, unless you have the program to
put into it, you're stuck. If a 555 fails, well, there's a tube of 50 in
my spares box. And I cna go to any number of suppliers anf buy one.
-tony
I'm with Tony here - consider this, the number of components on a 555
die vs the Aurdino are orders of magnitude less, and the size is much
larger for the 555 elements.
Cosmic radiation is one of the main causes of electronic failures, thus
a part with larger elements and fewer bits is going to be more reliable.
In my field we service video games from the early 70s (and up) - and
555s are amongst the most reliable parts found - far more reliable than
CPUs (1980s) for example...
John :-#)#
A metal-film resistor, used
below its ratings, will outlive any microcotnroller.
-tony
Well maybe (though no guarantee there), but the 555 would likely have the
same sort of lifetime as a microcontroller - arguably poorer.