I guess this is just not done for whatever reason. I hit Google and even after over 20 mins could not really find any information on point.
I've got a fair amount of .47uF and .68uF X1/X2 Metallized Polyester Film(I've got data sheets on a couple of them, these are all box) safety caps.
I want to use them to create a DAC reconstruction filter. I have not yet decided on the topology though. I'm thinking a 3 to 5 pole LC combined with a 3 pole Sallen Key active. I mean the caps would be perfect, high ratings, good D, not ceramic(The ceramic NP0 would be too small).
If they were not rated, I would not think twice, but I'm just wanting to make sure they won't cause problems based on their construction. Was there something done to enable them to be rated that would cause problems. The datasheets does not say, nor kind I find/see any complaints.
Ops forgot a data sheet:Okaya PA Series
NOTE: I added the x-capacitor tag, but I still feel the safety-capacitor tag would be better, or maybe a link. I think those Y caps feel discriminated against..:)
Best Answer
" Was there something done to enable them to be rated that would cause problems." No. "Are there any gotchas?" Other than possibly enough inductance to affect performance, No.
Safety rated capacitors are more robust than equivalent film or ceramic unrated parts. They also are almost always larger and more expensive, especially in a low-voltage application. But other than an ESL (Equivalent Series Inductance) that is much higher than that of a 25 V or 50 V part, I don't think there are other issues.