CommonModeLineChokes – EEStyles
Document 141-1
SCHEMATIC
TYPICALAPPLICATION
Low cost
VDE, IEC, UL, CSA compatible
3750 VRMS isolation between windings
UL approved Class 130°C insulation system
available (UL File E83628)
Industry-standard EE25 size
Wide range of available inductances and cur-
rent ratings
Coilcraft Designer’s Kit No. P202 contains sam-
ples of 8 standard EE and toroidal common mode
line chokes. To order, please contact Coilcraft.
Coilcraft common mode standard packages in-
corporate several features to help meet the re-
quirements of all major international safety
agencies. These include 2mm thick center
flanges and 3mm creepage and clearance from
all terminations to the core.
Common mode chokes are used to greatly re-
duce AC line conducted interference produced
by switching power supplies. This configuration
produces opposing magnetic fluxes in the core
that serve to cancel inphase noise signals ap-
pearing across the AC line.
This mode allows much more filtering capability
in a given core size than would be possible using
differential filtering alone. Use of common mode
chokes therefore 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 allows windings to be balanced within 1%
and features the cost effectiveness of standard
EE core styles.
Specifications subject to change without notice.
Document 141-1 Revised 6/6/95