Datasheet

3© 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)
Magnetic Permeability of Ferrite Material
Inordertoachievemostecientnoisereduction,itisimportanttoselectthematerialaccordingtothetargetfrequency
band.Dependingonitsmagneticpermeability,aparticularferritematerialwillbeeffectiveinacertainfrequencyband.
Aschematicrepresentationoftherelationshipbetweenthemagneticpermeabilityofeachmaterialandthecorresponding
effectivebandrangeisshowninFigure1.Materialswithhighermagneticpermeabilityareeffectiveinthelowerfrequency
range,whilethosewithlowermagneticpermeabilityareeffectiveinthehigherfrequencyrange.Thus,Mn-Znproductsare
mainlyusedforreducingconductionnoise,whileNi-Znproductsarecommonlyusedforradiationnoisecountermeasures.
Theeffectivefrequencyrangevariesdependingoncoreshape,sizeandnumberofwindings.Thisfrequencydependence
ofthemagneticpermeabilityasshowninthegureservesforreferencepurposesonlyanditshouldbetestedontheactual
devicetodetermineitseffectiveness.
S18H,S15H,10H,7H,5H,1400Land700LareKEMET’sproprietaryferritematerialnames.
Othermaterialscanalsobeavailableonrequest.
Figure 4 - Relationship between the magnetic permeability of each material and its effective frequency range
10 kHz
0
10,000
20,000
100 kHz 1 MHz 10 MHz 100 MHz 1 GHz
Effective Frequency Range
Magnetic Permeability
Ni-Zn Series
1400L
700L
S18H
S15H
10H
7H
5H
Mn-Zn Series
Lower magnetic permeability:
Higher noise suppression effect
in the higher frequency range
Higher magnetic permeability:
Higher noise suppression effect
in the lower frequency range