Even Intel used bad capacitors

[Lostgallifreyan]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in
news:478B0C87.5799F170@hotmail.com:

So we used 63V caps on a supply that was 67V off-load and we had ZERO
reliability problems with that. In fact it was one of the most reliable
products that the company ever made.

I was given an amp once, burnt cap in the PSU. 7 other caps were fine, and
the voltage was like yours, very slightly exceeding the cap spec. While most
survived, the failure was spectacular. It's worth uprating to limit the odds
to nearly zero because if it does fail, it might take out more than itself.

 

[Michael A. Terrell]

Eeyore wrote:

"Michael A. Terrell" wrote:

Eyesore wrote:

Yes but most kit isn't intended for military or aerospace use. Most deratings are
historically based AIUI and modern components really don't need it.

That's why most consumer electronics dies within two years.

No it doesn't.

Graham

Prove it, Ass. Between marginal components, the ROHS hoax and crappy
designers, like you, it doesn't stand a chance.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

[Lostgallifreyan]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in
news:478B0C87.5799F170@hotmail.com:

Yes but most kit isn't intended for military or aerospace use. Most
deratings are historically based AIUI and modern components really don't
need it.

Maybe true, maybe not. Consistency is better, but that just means makers can
claim better specs for a design. If they can make money by narrowing the
spec margin, they will. You still need to uprate, just not as much. And where
there is call for several similar parts with slightly varied specs, it is
sensible to uprate to one common spec and save with bulk buying.

 

[Lostgallifreyan]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in
news:478B837E.C935F50F@hotmail.com:

and/or run below rated voltage.

Utterly WRONG. This is pure myth.

It's logically correct. If we forget margin-pushing exercises, you have two
choices, lower, or higher. Running at lower voltage is obviously the better
choice out of those two. Not just better, but taking the other choice can
cause explosions.

 

[Clint Sharp]

In message
<0d5652b7-671f-40a4-be1b-194b7c5eeb97@i72g2000hsd.googlegroups.com>,
www.interfacebus.com <Interfacebus.Engineer@gmail.com> writes

On Jan 12, 1:00 pm, Leaking Caps <nob...@mixmin.net> wrote:
I haven't heard of this issue for a few years now
You've not been listening in the right places then.

--
Clint Sharp

 

[Prepair Ltd]

On Mon, 14 Jan 2008 15:58:35 GMT, Lostgallifreyan <no-one@nowhere.net> wrote:

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in
news:478B0C87.5799F170@hotmail.com:

Yes but most kit isn't intended for military or aerospace use. Most
deratings are historically based AIUI and modern components really don't
need it.


Maybe true, maybe not. Consistency is better, but that just means makers can
claim better specs for a design. If they can make money by narrowing the
spec margin, they will. You still need to uprate, just not as much. And where
there is call for several similar parts with slightly varied specs, it is
sensible to uprate to one common spec and save with bulk buying.

It also comes down to availability and whether an item is bulk produced or not.

Speccing a bulk-buy component against a similar one that is not in popular usage
will affect the price you'd pay.

Buying 105 Deg C rated caps where 85 Deg C will do the job with a decent margin
is not good purchase practice, but you may well find that 'your' component is
cheaper in the 105 deg C version simply because there is a huge volume going to
someone like LG or Samsung.


Peter
--
Peter A Forbes
Prepair Ltd, Rushden, UK
prepair@easynet.co.uk
http://www.prepair.co.uk
http://www.prepair.eu