Choke inductor

DC resistance AC is a simple way of saying, it can isolate and reduce the AC signal, or form a resonant circuit with resistor and capacitor, adjust the language and select the frequency. Inductance coil and capacitor in parallel can form LC tuning circuit. That is, if the natural oscillation frequency 0 of the circuit is equal to the frequency of the non AC signal, the inductive reactance and capacitive reactance of the circuit are also equal, so the electromagnetic energy oscillates back and forth between the inductor and the capacitor, which is the resonance phenomenon of the LC circuit. When resonant, the inductive reactance and capacitive reactance of the circuit are equivalent and reverse, so the inductive reactance of the total current of the circuit is small, and the current amount (refers to - 0 AC signal), so the LC resonant circuit has the function of selecting the frequency, and can select the AC signal of a certain frequency.

The higher the signal frequency is, the easier it is to be transmitted. However, the general signal lines have no shielding layer. These signal lines become very good antennas to receive all kinds of messy high-frequency signals in the surrounding environment. If these signals are superimposed on the original transmitted signals, they will even change the original transmitted useful signals and seriously interfere with the normal operation of electronic equipment, Therefore, it is necessary to reduce the electromagnetic interference (EM) of electronic equipment. Under the action of the magnetic ring, even if the normal and useful signal passes smoothly, it can suppress the high-frequency interference signal very well, and the cost is low. The magnetic rod inductance coil also plays an important role in over noise, screening signal, stabilizing current and suppressing electromagnetic wave interference.