Datasheet

TRA 1 Series
Application Note
http://www.tracopower.com Page 31 of 35
EMC considerations
Single Output Dual Output
Recommended circuit to comply EN55022 Class A Limits
Recommended PCB Layout with Input Filter
To: comply with EN55022 CLASS A following components are needed:
Model Component Value
TRA 1-05xx
TAR 1-12xx
C1 1µF/25V 1206 MLCC
L1 12µH SR0302MS/0.75A
TRA 1-24xx
C1 4.7µF/50V 1206 MLCC
L1 6.8µH SCD03021T/0.85A
Tolerance Envelopes Graph
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
.
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 commended to use a good 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.