INSTRUCTION MANUAL
PFE500F
Series
TDK-Lambda
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Output Voltage Adjustment by applying external voltage
By applying external voltage at the TRIM terminal, output voltage can be adjusted within the same output
voltage adjustment range as the output voltage adjustment by external resistor or variable resistor. For this case,
output voltage can be determined by the formula shown below.
Output Voltage = TRIM Terminal Voltage
x
Nominal Output Voltage
For applications other than the above, refer to the TRIM circuit as shown in fig.2-3 and determine external
circuit and components values.
12/21
+S
-S
+V
-V
TRIM
+
-
Load
R1
VR
Fig. 2-1 External Resistor Connection Example
+S
-S
+V
-V
TRIM
+
-
Load
Fig. 2-2 Output Voltage Adjustment by applying external voltage
Rederence
voltage
+S
-S
TRIM
Error amplifier
7.32k
W
1.225V
32.4k
W
1k
W
Fig.2-3 Internal TRIM Circuit (For the Reference)
