There's probably no difference.
Failure rates, absent abuse, are measured in FITS, where one FIT is
one failure per billion hours. Digital ICs are usually a few FITS for
simple stuff, numbers like 20 or 100 for an FPGA maybe. Some vendors
will supply numbers if you search around or ask directly.
Reliability does go down as temperature goes up, about 2:1 incease in
FITS per 10 degrees C. So if higher supply voltage makes the chips get
hotter, that could matter.
--
John Larkin Highland Technology, Inc
jlarkin at highlandtechnology dot com
http://www.highlandtechnology.com
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