10

© KEMET Electronics Corporation • P.O. Box 5928 • Greenville, SC 29606 (864) 963-6300 • www.kemet.com

A4002_EEV • 2/21/2014

Surface Mount Aluminum Electrolytic Capacitors – EEV Series, +105ºC

Therelationshipbetweentheleakagecurrentandvoltageappliedatconstanttemperaturecanbeshownschematicallyasfollows:

I

V

R

V

F

V

V

S

Where:

V

Ifthislevelisexceeded,alargequantityofheatandgaswillbegeneratedandthecapacitorcouldbedamaged.

V

Thislevelrepresentsthetopofthelinearpartofthecurve.

V

ThisliesbetweenV

Electrolyticcapacitorsaresubjectedtoareformingprocessbeforeacceptancetesting.Thepurposeofthispreconditioningistoensure

thatthesameinitialconditionsaremaintainedwhencomparingdifferentproducts.

Ripple Current (RC)

Themaximumripplecurrentvaluedependson:

• Ambient temperature

•Surfaceareaofthecapacitor(heatdissipationarea)

tanδorESR

• Frequency

Thecapacitor’slifedependsonthethermalstress.

Frequency Dependence of the Ripple Current

ESRand,thus,thetanδdependonthefrequencyoftheappliedvoltage.Thisindicatesthattheallowedripplecurrentisalsoafunction

ofthefrequency.

Temperature Dependence of the Ripple Current

Thedatasheetspecifiesmaximumripplecurrentattheuppercategorytemperatureforeachcapacitor.