EEV107M035A9HAA Datasheet, PDF (8/16 Pages) Kemet Corporation – Surface Mount Aluminum Electrolytic Capacitors EEV Series, +105ºC

Surface Mount Aluminum Electrolytic Capacitors – EEV Series, +105ºC
C_o
R_e
L
Equivalent Series Resistance (ESR)
Equivalent Series Resistance is the resistive component of the equivalent series circuit. ESR value depends on frequency and
temperature and is related to the tan δ by the following equation:
C_e
ESR = Equivalent Series Resistance (Ω)
ESR =
tan δ
2πf ESC
tan δ = Dissipation Factor
ESC = Equivalent Series Capacitance (F)
f = Frequency (Hz)
Tolerance limits of the rated capacitance must be taken into account when calculating this value.
Impedance (Z)
C_o
R_e
L
Impedance of an electrolytic capacitor results from a circuit formed by the following individual equivalent series components:
C_o R_e
L
C_e
C_e
C_o = Aluminum oxide capacitance (surface and thickness of the dielectric)
R_e = Resistance of electrolyte and paper mixture (other resistances not depending on the frequency are not considered: tabs, plates,
etc.)
C_e = Electrolyte soaked paper capacitance
L = Inductive reactance of the capacitor winding and terminals
Impedance of an electrolytic capacitor is not a constant quantity that retains its value under all conditions; it changes depending on
frequency and temperature.
Impedance as a function of frequency (sinusoidal waveform) for a certain temperature can be represented as follows:
Z [ohm]
1000
100
10
Re
1
0.1
0.1
A
1/ω Co
1
10
1/ω Ce
B
100
1000
ωL
C
10000
F [KHz]
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