a
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TDK-Lambda
CN-A24 Series
Instruction Manual
Output Voltage Adjustment by External Resistor or
Variable Resistor
(1) In case of adjusting output voltage lower
(1-1) Allowable maximum output current = rated
maximum output current of specification.
(1-2) Connect an external resistor Radj(down)
between the TRM terminal and –S terminal.
Fig.2-1 Connection for Output Voltage Trim Down
(1-3) Equation of external resistor and output voltage
Radj(down)
: External adjustment resistor
Δ(%)
: Output voltage change rate against
nominal output voltage
ex) When setting 5V Model to 4.5V output,
Δ(%) should be set at 10%.
Below graph is relation Δ(%) and value of
external resistor.
Fig.2-2 Δ(%) vs. Radj(down)
(2) In case of adjusting output voltage higher
(2-1) Allowable maximum output current = maximum
output power ÷ adjusting output voltage.
(Becomes less than maximum output current of
specification.)
(2-2) Connect an external resistor Radj(up) between
TRM terminal and +S terminal.
Fig.2-3 Connection for Output Voltage Trim Up
(2-3) Equation of external resistor and output voltage
Vo
: Nominal output voltage
Radj(up)
: External adjustment resistor
Δ (%)
: Output voltage change rate against
nominal output voltage
ex) When setting 5V Model to 5.5V output,
Δ(%) should be set at 10%.
Below graph is relation Δ(%) and value of
external resistor.
Fig.2-4 Δ(%) vs. Radj(up)
1
10
100
1000
0
2
4
6
8
10
R
ad
j(
do
w
n
)[
kΩ
]
10
100
1000
10000
0
5
10
15
20
R
ad
j(
up
)[
kΩ
]
[ ]
W
÷÷
ø
ö
çç
è
æ
-
D
=
k
down
Radj
2
(%)
(%)
100
)
(
[ ]
W
÷÷
ø
ö
çç
è
æ
-
D
-
D
´
D
+
=
k
Vo
up
Radj
2
(%)
(%)
100
(%)
225
.
1
(%))
(%)
100
(
)
(
change rate against
nominal output voltage[%]
5V
12V
24V
change rate against
nominal output voltage[%]
+V
-V
+S
-S
TRM
＋
-
Load
CN100A24
Radj(down)
+V
-V
+S
-S
TRM
+
-
Load
CN100A24
Radj(up)
CN-A24
CN-A24
