Datasheet

2© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard E5009_B-20 • 9/18/2018
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
EMI Core – B-20 Bead Cores for Round Cables for Low & High Frequency (Bare & coated)
Core Material and Effective Frequency Range
TherearetwoferritematerialoptionsforKEMET
EMICores:Nickel-Zinc(NiZn)andManganese
Zinc(MnZn).Eachcorematerialhasadifferent
resistanceandeffectivefrequencyrange.The
MnZn core material has a lower resistance
comparedtotheNiZn;therefore,adequate
insulationisrequiredbeforeuse.
TheNiZncorematerialistypicallyeffectivefor
frequenciesintheMHzbandrangesuchasthe
FM-band,whiletheMnZncorematerialistypically
effectiveforthekHzbandrangesuchastheAM-
band.SeeFigure1.
It is recommended to measure the actual
frequencyrangeeffectivenessinthetarget
application.
Environmental Compliance
AllKEMETEMIcoresareRoHScompliant.
Dimensions – Millimeters
OD
ID
T
See Table 1 for dimensions
Impedance (Ω)
Frequency (MHz)
AM band range FM band range
Mn-Zn series core
Ni-Zn series core
1,000
100
10
1
0.01 0.1 1 10 100 1,000
Figure 1 – Effective band range of Mn-Zn and Ni-Zn ferrite core material.
(Representative example, measured with same-dimension ring core)