low leakage caps

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would the attached be classed as low leakage, or would it need to be less.


i have a couple of 1uf caps in an amp im working on that are below the threshold of what is stated in the spec(reading around 0.25uf) and need to replace them.
the drawing denotes them as low leakage, so i need to know if these would be suitable


just as a note what would be classed as low leakage for my future reference many thanks
 
thanks, i dont have a problem choosing or sourcing.
The existing have A(LL) on them, but i cant find a reference to to this


this is where they are placed in the circuit.(C401) is one of them, the other is its opposite on the other channel.
 

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Nichicon defines low leakage as "After 1 minute (for case size 10 = 12.5 or smaller) or 2 minutes
(for case size 10 = 16 or larger) application of rated voltage at 20°C, leakage current is not more
than 0.002CV or 0.2 (µA) whichever is greater."

Other mfrs may differ. You would have to analyze the circuit to determine how much leakage is acceptable.
Certainly a good film type would be sufficiently low in most cases, if its physical size fits.
 
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A capacitor in a circuit has a function. Being polarized is a limitation, not a feature.
A nonpolar (unpolarized) film capacitor can serve just as well if not better, provided that
its larger size and higher cost is acceptable.

Electrolytic capacitors are used primarily where their limitations (high leakage, loose tolerance,
poor lifetime, poor reliability) must be tolerated for various other reasons (small size, low cost).
As you have found, electrolytic types have poor reliability. Film types would not have done this.
 
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How much room is available for the new part? Polypropylene film is preferred in most cases,
but such a part will be larger in physical size than an electrolytic type. It may be necessary
to use an electrolytic just because of the space available on the board.
 
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The problem with fitting film types is that you probably will not get them to fit the board neatly, not if the originals have a 2.5mm lead pitch.

Tbh I would be totally happy to fit good commercial quality electrolytics as was originally fitted.
 
Tbh I would be totally happy to fit good commercial quality electrolytics as was originally fitted.

The original question was because the old caps were low leakage types, and he didn't know what to do.
He also thought that polarized capacitors were necessary, to function properly in the circuit.
 
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I use Kemet R82EC4100Z370K or Epcos B32529D1105J as 5mm pitch replacement for vintage electrolytics on the signal path. They aren't the best audio capacitors, but still better than electrolytics while still fitting on most of the boards. Wima MKS02/1.0/50/20 have the tight 2.5mm pitch.