EMI Filter Module (18A)

The EMI filter PCB specification is FR4 50X50X1.6MM, which can be combined into a multi-stage EMI filter, the shortest design of the large current line, the short path, can withstand larger currents, and has less interference to the outside world, which is better than the design of the general long stripboard. The 50X50MM square plate has high mechanical strength, is not easy to bend and deform, and it is convenient to add a shielding cover.

Common mode inductors have three specifications of 2A, 4A, and 18A.

18A: EMI filter, load power 3960W.

This module can be used with a decoder or a power amplifier to filter the high-frequency noise of the power supply, eliminate interference from the mains, and purify the power supply. It can significantly improve the sound quality of the power amplifier, increase the resolution and make the background quiet.

The input GND needs to be connected to the ground wire of the power cord, and can also be connected to the chassis shell. Depending on the specific situation, please pay attention to the direction when soldering the 4A common mode inductor. Please install and solder according to the label on the circuit board and the baby picture.

The following are some common sense of high-frequency electromagnetic interference EMI filters.

For high-frequency electromagnetic interference (EMI), generally, three technologies can be used for power filtering to suppress interference noise. In actual use, two or even multiple technologies are often mixed. They are:

1. Add a capacitor between the live wire and the neutral wire of the power supply, that is, the X capacitor. Choose X2 type, the main function is to eliminate common mode interference, the capacity range is 0.01UF---0.47UF.

2. Add a capacitor between the power line and the ground line, that is, the Y capacitor. The Y2 type is selected to mainly eliminate the interference of cross-talk, and the capacity range is 2200pF～0.1μF. In order to reduce the leakage current, the capacitance should not exceed 0.1μF, this circuit board chooses 0.01UF.

3. Common mode suppression, common mode inductance (suppression coils on the two power lines), when the rated current is large, the wire diameter of the common mode choke coil should be correspondingly increased so as to be able to withstand a large current. In addition, an appropriate increase in inductance can improve the low-frequency attenuation characteristics. This line uses 10MH