Datasheet

TMH Series
Application Note
http://www.tracopower.com Page 49 of 53
EMC considerations
R
load
C1
+V
out
-V
out
+V
in
-V
in
+V
out
-V
out
+V
in
-V
in
+V
in
-V
in
R
load
+V
in
- V
in
C1
-V
out
+V
out
-V
out
COM
R
load
+V
out
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
TMH 05xx C1 3.3μF/25V 1206 MLCC
TMH 12xx, TMH 24xx C1 1μF/50V 1206 MLCC
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 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.