Capacitor Leakage current

[nonoise]

Interesting article on AL capacitors from Epcos
Regarding leakage current and other phenomena
http://www.epcos.com/web/generator/W...,a=490592.html

[AndrewT]

Hi,
Whenever I check electrolytic leakage current and compare to the manufacturer's specification for leakage, I get results that are not similar.

What are the units used in the standard leakage formula?

Leakage = factor * V * C
usually I see spec quoting IL=0.02VC

using Amperes and Volts and Farads, I often get the factor coming out better than F<=0.00001. This seems so much less leakage that I always suspect I am doing something wrong.

Help !

[Bill_P]

Nippon Chemicon LXZ ALUMINUM ELECTROLYTIC CAPACITORS
Leakage Current
I=0.01CV or 3uA, whichever is greater.
Where, I : Max. leakage current (uA),
C : Nominal capacitance (uF),
V : Rated voltage (V)
(at 20C after 2 minutes)

Measuring temperature and voltage influence the leakage
current. The leakage current shows higher values as the
temperature and voltage increase.

In general, the leakage current is measured at 20C by applying
the rated voltage to capacitor through a resistor of 1000 Ohms
in series. The leakage current is the value several minutes later
after the capacitor has reached the rated voltage. The catalog
prescribes the measuring temperature and time.

The text above is from Nippon Chemicon publications.
The last thing capacitor manufacturers want is part
rejection based on leakage. Their parts typically
perform 100 times better for leakage than the
datasheet specifies.

Example 1000uF 16V LXZ Capacitor Leakage
I=0.01(1000)16=160uA

[AndrewT]

A couple of recent examples using cheap sub min electrolytics.
470uF 16V 0.085uA leakage.
100uF 10V 0.2uA leakage.