Datasheet

2© KEMET Electronics Corporation • KEMET Tower • One East Broward Boulevard E5001_ESD-R • 9/13/2018
Fort Lauderdale, FL 33301 USA • 954-766-2800 • www.kemet.com
EMI Core – ESD-R Toroidal Cores for Round Cables for Low & High Frequency (Bare, coated & with case)
Part Number System
ESD- R- 10 D
Series Shape Type
CoreSize
OuterDimensionCode(mm)
InternalManagementCode
ESD- Ring SeeTable1
Turns and Impedance Characteristics
WhenthedesiredperformanceofanEMIcorecannotbe
obtainedwithasinglepassthroughthecore,theimpedance
characteristicscanbechangedwithmultipleturns.
Aturniscountedbythenumberoflead-wirewindingswhichpass
throughtheinnerholeofthecore.Windingsontheoutsideofthe
core do not count.
SeeFigure1forexamplesofone,two,andthreeturns.
Addingturnswillresultinhigherimpedancewhilealsolowering
theeffectivefrequencyrange.
SeeFigure2foranexample.
Core Material and Effective Frequency Range
TherearetwoferritematerialoptionsforKEMET
EMICores:NickelZinc(Ni-Zn)andManganese
Zinc(Mn-Zn).Eachcorematerialhasadifferent
resistanceandeffectivefrequencyrange.The
MnZn core material has a lower resistance
comparedtotheNi-Zn;therefore,adequate
insulationisrequiredbeforeuse.
TheNi-Zncorematerialistypicallyeffective
forfrequenciesintheMHzbandrangesuchas
theFM-band,whiletheMn-Zncorematerialis
typicallyeffectiveforthekHzbandrangesuchas
theAM-band.SeeFigure3.
It is recommended to measure the actual
frequencyrangeeffectivenessinthetarget
application.
3T2T1T
Figure 1 – How to count turns
Impedance Increase
Resonance point changes to lower band
3T
2T
1T
Impedance (Ω)
Frequency (MHz)
10,000
1 10 100 1,000
1,000
100
10
1
Figure 2 – Relationship between impedance and turn count.
(Representative example: ESD-R-16C)
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 3 – Effective band range of Mn-Zn and Ni-Zn ferrite core material.
(Representative example, measured with same-dimension ring core)