8 Oct
2016
8 Oct
'16
9:39 a.m.
On 10/08/2016 05:18 AM, Rob Jarratt wrote:
I have an RD53 disk drive. When I plugged it in the
other day something blew
up, smoke etc. I found that it was a tantalum capacitor on the motor control
board that had gone. I suppose I am wondering if just replacing it is a good
idea, could the failure be a symptom of another problem, could it have
damaged something else? I realise that without a schematic it may be
difficult to comment, but I suppose it is more a question about what can
cause these caps to fail?
A WELL-KNOWN problem with Tantalum caps is that if run in
equipment for some time, then put on the shelf for some
years, then powered up again, the caps will fail, often
spectacularly. Sometimes, in things like memory boards, you
will have to replace many caps. Likely, just the cap is bad,
if it is on an externally-supplied power rail. Supposedly,
if you were to ramp up the supply voltage slowly, it would
allow the cap's dielectric to reform gracefully.
Jon