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TDK-Lambda
CN-A110 Series
Instruction Manual
(3)
To adjust output voltage for whole range
Resister values, as well as, connecting methods for external
resistor (R1) and external variable resistor(VR) are described
below.
5V 12V 15V 24V
R1 5.6k 5.6k 5.6k 5.6k
VR
2k
5k
5k
10k
unit:[
Ω
]
External resistor
：±
5% Tolerance
External variable resistor
：±
20% Tolerance
with end resistance below 1%
Table 2-1 Values of External Resistor and Variable Resistor
Vo :
–
10% - +20%(5V)
Vo :
–
10% - +10%(12V,15V,24V)
Fig.2-5 Example of Connecting External Resistor
For applications other than the above, refer to the TRM
circuit as shown in fig.2-6 and determine external circuit and
components values.
Fig.2-6 Internal TRM Circuit (For the Reference)
3. Maximum Output Ripple and Noise
Measured value according to the specified methods based on
JEITA-9141 (Clause 7.12 and clause 7.13) which is described
in the following.
Connect according to fig.3-1 and measure. Connect
capacitors (C2 : ceramic capacitor , C3 : electrolytic capacitor)
at 50mm distance from the output terminals. Measure at
ceramic capacitor (C2) terminals as shown in fig. 3-1 using
coaxial cable with JEITA attachment. Use oscilloscope with
100MHz frequency bandwidth or equivalent.
Fig.3-1 Measurement of Maximum
Output Ripple and Noise
Take note that output ripple voltage and output spike noise
may vary depending on PCB wiring design.
Generally, increasing capacitance value of external capacitor
can reduce output ripple voltage and output spike noise.
4. Maximum Line Regulation
Maximum value of output voltage change when input voltage
is gradually varied (steady state) within specified input voltage
range.
5. Maximum Load Regulation
Maximum value of output voltage change when output
current is gradually varied (steady state) within specified
output current range.
When using at dynamic load mode, audible noise could be
heard from the power module and output voltage fluctuation
might increase. A thorough pre-evaluation must be performed
before using this power module.
6. Baseplate Temperature vs. Output
Voltage Drift
Output voltage drift is defined as the rate of voltage change when
only baseplate temperature is changed during operation.
+V
-V
+S
-S
+
-
Load
CN - A110
1.5m 50
Ω
Coaxial cable
Oscilloscope
JEITA Attachment
R:50
Ω
C:4700pF
R
C
As short as
possible
C2
C3
100MHz
Bandwidth
50mm
+S
-S
+V
-V
TRM
+
-
Load
R1
VR
C3
C2
CN -A110
1k
Ω
1.225V
Reference
Voltage
1k
Ω
OP amp at Voltage monitor
+S
TRM
1k
Ω
-S