Many of us have seen electronic equipment last longer then one year. Some of use even have still working antiques with old eletro caps. Those short lifetimes assume a worse case, usually with a very high ripple current. IOf you can reduce the ripple the MTBF goes up.
One question: How does one avoid using electrolytic caps if you need (say) 1,000uF or even 100uF. Those would be some mighty big film caps. On Fri, Nov 25, 2011 at 10:06 PM, <saidj...@aol.com> wrote: > Electrolytic caps have an extremely poor lifetime (MTBF). Sanyo on their > website state "50K Hrs at 50C". > > This means only 6250 MTBF hours at 80C for one single cap. MTBF gets worse > the more caps are being used of course. I have seen some Panasonic > electrolytics state only 2000 hours MTBF at temperature in their datasheets. > > That's not even one year before a mean failure occurs making these useless > in high-reliability applications. > > Note also that caps in high AC current situations (Buck DC-DC switcher > input cap for example) will self heat due to internal resistance, making > things > even worse. This is probably one of the main failure reasons for PC > motherboards. > > And that's with name brand parts, it's even worse if one ends up buying > counter-fit or non-name-brand Electrolytics. > > Some of our competitors use Electrolytics all over the place (we don't use > any electrolytics) - that's been good for our business. > > bye, > Said > > > In a message dated 11/24/2011 17:08:42 Pacific Standard Time, > li...@lazygranch.com writes: > > I'm not familiar with rubycon caps. The low ESR large value caps are > "organic semiconductor." OSCON is a common brand from Sanyo. Finding the > ultimate cap is nearly as much fun as finding the ultimate LDO. Check > out Nichicon. Or you can stick with the Rubycon. Glancing at their > website, they seem to copy the Nichicon product line. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.