PAH50S48-2.5 TDK Corporation, PAH50S48-2.5 Datasheet - Page 79

• Manufacturer Part Number: PAH50S48-2.5
• Manufacturer: TDK Corporation

（2） Secondary (output side) control
（A） Series Operation in High Output Voltage
（B） ± Output Series Operation
PAH
 Parallel Operation
Parallel Operation can not be used.
 Series Operation
Series Operation is possible for PAH200H Series.
For the number of maximum series connection, please
contact us
 Operating Ambient Temperature
According to ambient temperature, output load should
derated accordingly (refer to Mounting Method & Terminal
Condition). There is no restriction on mounting direction
but there should be enough consideration for airflow so
When Series Operation is used to obtain Higher Out-
put Voltage, a bypass diode is needed to prevent the
reverse voltage (refer Fig12-1.) The selection guide for
this bypass diode is described below :
Condition of selection, bypass diode D1, D2
1. Peak Repeated Reverse Voltage
VRRM≧duplicate of nominal output
voltage of the power supply.
2. Average output current
Io≧duplicate of nominal output current
of the power supply.
3. Forward voltage
Output reverse maximum applied voltage: 0.6VDC and
below
Fig.12-1 Series Operation for High Output Voltage
When +load and –load is completely separated the
bypass diode is not required.
VF≧The lowest
(schottky barrier diode and equivalent)
200H
(output side)
Fig.12-2 ± Output Series Operation
Secondary
＋S
＋V
−V
−S
＋S
＋V
−V
−S
＋S
＋V
−V
−S
＋S
＋V
−V
−S
Fig.10-1 CNT Connection
+
+
+
+
D1
D2
＋Vin
CNT
−Vin
PAH200H
series
Load
＋
−
＋
−
＋
−
Load
Load
that heat does not accumulate around the power module
vicinity.
Determine external components configuration and mount-
ing direction on PCB such that air could flow through
power module at forced air cooling or convection cooling.
For better reliability, derating of ambient temperature is
recommended. For details on derating, refer to “Mounting
Method & Thermal Condition” .
 Operatin Ambient Humidity
Take note that moisture could lead to power module ab-
normal operation or damage.
 Storage Ambient Temperature
Abrupt temperature change would cause condensation
built-up that leads to poor solderability of terminals of the
power supply.
 Storage Ambient Humidity
High temperature and humidity can cause the terminals
on the module to oxidize. The quality of the solder will be-
come worse.
 Cooling Method
Forced air cooling is recommended. Convection cooling is
also possible. For the details of derating, refer to “ Mounting
Method and Thermal condition”
 Ambient Temperature vs. Output Voltage Drift
Temperature coefficient is defined as the rate of voltage
change when ambient temperature is changed during op-
eration.
 Withstand Voltage
This power module is designed to have a withstand volt-
age of 1.5kVAC between input and output. When con-
ducting withstand voltage test during incoming inspection,
set the current limit value of the withstand voltage testing
equipment to 20mA. Furthermore, avoid throw in or shut
off of the testing equipment when applying or when shut-
ting down the test voltage. Instead, gradually increase or
decrease the applied voltage. Take note especially not to
use the timer of the test equipment because when the tim-
er switches the applied voltage off, impulse voltage which
has several times the magnitude of the applied voltage is
generated causing damage to the power module.
Short the output side as shown in fig.19-1.
 Insulation Resistance
Use DC insulation tester (MAX 500V) between output and
Fig.19-1 Withstand Voltage Test for Input-Output
1.5kVAC 1minute (20mA)
Isolation tester
Withstand
Voltage tester
500VDC
AC
+Vin
CNT
−Vin
+Vin
CNT
−Vin
TRM
TRM
-Vin
-Vin
-Vin
-Vin
+V
+V
+V
+V
-S
-S
-S
-S
B-221
PAH