© Coilcraft, Inc. 2007
Specifications subject to change without notice.
Please check our website for latest information.
Common Mode Line Chokes – EE Styles
Document 141-1
Document 141-1 Revised 02/06/06
• Low cost
• VDE, IEC, UL, CSA compliant
• 3750 Vrms isolation between windings
• Constructed with UL approved Class 130°C insula-
tion system (UL File E83628)
• Industry-standard EE25 size
• Wide range of available inductances and current
ratings
Coilcraft Designer’s Kit No. P402 contains samples of
eight standard EE and toroidal common mode line
chokes. To order, contact Coilcraft or purchase on-line
at http://order.coilcraft.com.
Coilcraft common mode standard packages incorpo-
rate several features to help meet the requirements of
all major international safety agencies. These include
2 mm thick center flanges and 3 mm creepage and
clearance from all terminations to the core.
Common mode chokes are used to reduce AC line
conducted interference produced by switching power
supplies. This configuration produces opposing mag-
netic fluxes in the core that serve to cancel in-phase
noise signals appearing across the AC line.
This mode allows much more filtering capability in a
given core size than would be possible using differen-
tial filtering alone. Use of common mode chokes there-
fore reduces component count as well as inductor size.
Combining both common and differential mode chokes
gives the power supply designer the added flexibility
required to adjust the filtering to meet FCC, VDE, and
other requirements as well as optimize the circuit for
the particular noise levels and frequencies produced by
each power supply design.
The Coilcraft packaging of common mode chokes al-
lows windings to be balanced within 1% and features
the cost effectiveness of standard EE core styles.
Schematic Typical Application
AC
input
2 2
99
4 4
77
0.1 µF 0.1 µF
0.005 µF
0.005 µF