INSTRUCTION MANUAL
CHVM2 Series
TDKLambda
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■ Vref pin (standard voltage output)
When adjusting the output voltage with an adjustable resistor, this pin is used. Vref has a standard output
voltage of 4V. In this case, use an external resistor with a resistance of 5KΩ.
The resistance(the margin of error) of external adjustable resistor will affect the setting value of Vref pin voltage,
so use a resistor with an accuracy of 5KΩ±5%.
The type of adjustable resistor will not matter, however one with a well temperature coefficient is recommended.
■ Temperature derating
When using the product where the ambient temp. is higher than 50℃, follow the derating graph below.
The minimum load resistance is set for each series. When using higher than 50℃, set the load resistance
high by following the below graph.
■ Protection against reverse connection
The converter may break if the polarities are reversed. If there is a possibility in which the connections maybe
reversed, connect a diode and fuse to the input pin like below.
■ Recommended soldering conditions
Soldering conditions for each part is as follows:
(1) Soldering iron
340 360°C
5 seconds
(2) Dip solder bath
230 260°C
10 seconds
10/11
Vout (com)
Vcont
Vref
Vref voltage : 4
±
0.3V
3
4
Standard
voltage
origin circuit
External adjustable resistor (5.0K
Ω
)
6
CHVM Series
100
80
60
40
20
0
-20 -10 0 +10 +20 +30 +40 +50 +60
O
utp
ut
de
ra
tin
g r
ate
Ambient temp. (
℃
)
Start up is possible in this area . However the reliability
is not guaranteed .
(%)
12V
+
F1
+
Vin
-
Vin
CHVM
D1
