[colug-432] What causes electronics to expire?

[Rob Funk]

On Thursday, December 13, 2012 12:31:46 PM Joshua Kramer wrote:
> So as it turns out, the external enclosure in which I had my 500GB drive,
> is flaky.

> What's interesting is, for the past 18 months or so I've kept this
> enclosure in a cool, dark closet... and I've only moved it once every 1-2
> weeks to do backups.  And I only plug it into a UPS-protected outlet.
> 
> So I wonder what, barring an external physical event, causes a transistor
> or two to work one day, and then the next, say, "you know what?  I've
> had enough on/off cycles in my lifetime, I quit!"

It's mostly about the physical materials. Most often it's a capacitor, 
since the insulator inside breaks down over time. (Sometimes faster than it 
should.) It could also be a connection (like a solder joint) getting just 
enough corrosion to increase its resistance up to a significant level.

The transistors themselves don't tend to break down over time like that 
(they're essentially made of rock!), but they are usually sensitive to 
voltage surges, such as from discharging static electricity.