Q&A(FAQ) What is EMI filter recommended for DC-DC converter?
Fig. 1 shows an external noise filter that reduces line-conducted noise for a DC-DC converter.
| No. | Parts No. | Components | Note |
|---|---|---|---|
| 1 | C1 | Ceramic capacitor | Low impedance (Please refer to the instruction manual in the catalog) |
| 2 | C2 | Electrolytic capacitor | Low impedance (please see instruction manual on catalogue) |
| 3 | C3 | Ceramic capacitor | Low impedance (recommended value: 4.7uF) |
| 4 | C4 | Ceramic capacitor | Low impedance (recommended value: 1000pF) |
| 5 | L1 | Common mode coil | High leakage inductance (recommended: main 14mH, leakage 240uH) |
The wiring method, component placement, and other conditions can affect line-conducted noise.
Please evaluate the unit under end-use conditions before using it.
*Be careful with capacitor C4. Noise coupling from input to output increases when C4 is used.