Blown Tantalum Capacitor Advice

[Jon Elson]

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