Datasheet

Application Note
Created by Traco Electronic AG Arp. www.tracopower.com Date: January 4
th
, 2011 / Rev.: 1.4 / Page 37 / 44
20W, Single and Dual Output
EMC considerations (Continued)
Suggested schematic for EN55022 conducted emission Class B limits
Recommended layout with input filter
To comply with conducted emissions noise (EN55022 CLASS B) following components are needed:
TEN 20-242x WIN
Component Value Voltage Reference
C1 4.7μF 50V 1812 MLCC
C3, C4 1000pF 2KV 1808 MLCC
L1 450μH ---- Common Choke, P/N: TCK-048
TEN 20-482x WIN
Component Value Voltage Reference
C1, C2 2.2μF 100V 1812 MLCC
C3, C4 1000pF 2KV 1808 MLCC
L1 325μH ---- Common Choke, P/N: TCK-050
This Common Choke L1 has been define as follows:
■ TCK-048
L: 450μH ±35% / DCR: 25m, max
A height: 9.8 mm, Max
■ TCK-050
L: 325μH ±35% / DCR: 35m, max
A height: 8.8 mm, Max
■ Test condition: 100KHz / 100mV
■ Recommended through hole: Φ0.8mm
■ All dimensions in millimeters