EMI Core

5

EMI Cores

Ring Type

●All specifications in this catalog and production status of products are subject to change without notice. Prior to the purchase, please contact NEC TOKIN for updated product data.

●Please request for a specification sheet for detailed product data prior to the purchase.

●Before using the product in this catalog, please read "Precautions" and other safety precautions listed in the printed version catalog.

9634ESDVOL09E1003E1

■Effective band range depending on core material

 There are two materials of ferrite, Ni-Zn series and Mn-Zn series. Ni-Zn series is effective

for MHz band range such as FM band while Mn-Zn series is effective for kHz band range.

 Note that above effective band range is a reference only. Examination of effectiveness

with actual instrument is necessary.

 As Mn-Zn series has lower resistance compared to Ni-Zn series, make sure to provide

adequate insulation before use.

■Characteristics and how to count turns

 Number of turns are counted by how many times the lead wire passes through the inner

hole of the core. Do not count the number of lead wire winding outside the core, as it results

in different turn count. (Fig. 1)

 When desired performance can not be obtained just by 1 turn, impedance characteristics

value can be raised by increasing the turn. In this case, the effective frequency band should

be checked that it is in the desired range as adding turns results in lowering down the

effective band range. (Fig. 2)

Tips on EMI Core Usages

1

10000

1000

100

10

1T

2T

3T

1

10

100

1000

Frequency (MHz)

（Representative Example：ESD-R-16C）

Fig.1 How to count turns

Fig.2 Relationship between impedance and turn counts

1Ｔ

2Ｔ

3Ｔ

Resonance point changes to lower band

*Number of lead wire wound outside the core + 1

= Number of read wire passes through the inner

hole of the core

= Turn count

Mn-Zn series vs Ni-Zn series｜Z｜-f Characteristics (representative example)

AM band range

FM band range

(measurement condition: measured with same-dimension ring core)

1

10

100

1000

0.01

0.1

1

10

100

1000

Frequency (MHz)

Mn-Zn series core

Ni-Zn series core

Fig.3 Effective Band Range of Mn-Zn series / Ni-Zn series ferrite