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Typical Connection
For applications that require meeting EMC standards,the diagram above 6. Recommended values for components are:
7. Thedrawingsbelowshowtypicalboardlayoutsforthe EMC/
EMI circuit shown above (one for single output models and
one for dual output units).
illustrates a typical connection of the MD100xERWseries.The units
do not require external components to operate as specified.Some notes
on this diagram (starting with the input circuit) are:
Component
MOV
LDM1
TVS
C1
5 VIN
---
---
12 VIN
---
---
24 VIN
S14K35
56 µH
48 VIN
S14K60
56 µH
8. In many applications simply adding input/output
capacitors will enhance the input surge protection
and reduce output ripple sufficiently. The value of
the input capacitor can range from 1ꢁ µF to 1ꢁꢁ µF,
depending on the needs of the application. The output
capacitor would typically be 1ꢁꢁ µF.
9. The capacitor CS provides additional output filtering.
If used, a value of 1ꢁ µF to 2ꢁ µF is recommended. This
capacitor is not required for specified operation.
1. An external fuse should be used in all power module applications.
The recommended fuse is shown in the model chart on page 2.
2. To protect against a surge,an external MOV is recommended on the
input. A suggested value is given in the table at right.
3. To protect against voltage spikes, it is recommended that a TVS be
used on the input. A suggested value is given in the table at right.
4. ThecapacitorCS isrequiredtomeetallspecificationsonsingleoutput
units.
5. The output filtering capacitor (C4) is a high frequency,low resistance
electrolytic capacitor. Care must be taken in choosing this capacitor
not to exceed the capacitive load specification for the unit. Voltage
derating of capacitors should be 8ꢁꢀ or above.
SMCJ13A
SMCJ28A
SMCJ48A
SMCJ90A
680 µF/16V 680 µF/25V 330 µF/50V 330 µF/100V
4.7 µF/50V
12 µH
4.7 µF/50V
1nF/2 kV
C2
LDM2
C3
4.7 µF/50V 4.7 µF/100V 4.7 µF/100V
12 µH
4.7 µF/50V
1nF/2 kV
12 µH
12 µH
4.7 µF/50V 4.7 µF/100V
1nF/2 kV
CY
1nF/2 kV
CS
10 µF - 22 µF
C4
100 µF
100 µF
100 µF
100 µF
Typical Board Layout: With External Filter/Surge Components for Single Output Unit
Typical Board Layout: With External Filter/Surge Components for Dual Output Unit
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