Re: General advice on replacement of old decoupling tantalum capacitors (by new tants or alum. lytics).

Fabio Trevisan

Thank you all for your answers,
I summarize then the outcome, which I will follow.

So, Regarding substitution of tantalum capacitors, as a general advice:

1. Nothing wrong with the tantalum caps "per se", as long as one observes
at least 1/2 to 1/3 voltage derating (a practical recommendation that
hasn't been known - or followed - by Tek, back then).

2. It IS recommended to replace all power decoupling tants (i.e. connected
directly to power rails) that are not derated as per criteria above. Other
than that, it's not strictly necessary to blindly replace tantalum
capacitors (i.e. just because they're old, as they're not subject to
"dry-out" effect as their alum. counterparts).

Kindest Regards to all,


2017-06-28 2:45 GMT-03:00 @KO3Y [TekScopes] <

I'd tend to agree on bad tantalums. Replace them with modern equilivants
not electrolytic capacitors. Given the age of the equipment, the
replacement will likely outlive you!
I am not a fan of blindly replacing all ecaps or tants. That thinking does
not usually consider the reliability of the replacement process.

Join to automatically receive all group messages.