Datasheet

Application Note
Created by Traco Electronic AG Arp. www.tracopower.com Date: December 5
th
, 2011 / Rev.: 1.0 / Page 18 / 22
1W SINGLE
EMCconsiderations
Recommended circuit to comply EN55022 Class A Limits
Recommended PCB Layout with Input Filter
To: comply with EN 55022 Class A following components are recommended:
Model Component Value
C1 1µF/25V 1206 MLCC TRV 1-05xx &
TRV 1-12xx
L1 12µH SR0302MS/0.75A
C1 4.7µF/50V 1206 MLCC
TRV 1-24xx
L1 6.8µH SCD03021T/0.85A
ToleranceEnvelopesGraph
InputSourceImpedance
The power module should be connected to a low ac-impedance input source. Highly inductive source impedances
can affect the stability of the power module. In applications where power is supplied over long lines and output
loading is high, it may be necessary to use a capacitor at the input to ensure startup.
Capacitor mounted close to the power module helps ensure stability of the unit, it is recommended to use a good
high quality low Equivalent Series Resistance (ESR < 1.0Ω at 100 KHz) capacitor of a 2.2µF for the 5V input
devices, a 1.0µF for the 12V input devices and a 0.47µF for the 24V devices.
0% 20% 40% 60% 80% 100%
Output Voltage(%)
Output Load Current (%)
M
a
x
.
T
y
p
.
+5%
+10%
+15%
Vnom
-5%
-10%
+20%
+5%
+10%
+15%
Vnom
-5%
-10%
+20%
M
i
n
.