EMI mobile phone distribution, sharing, sharing, sharing, sharing, sharing, sharing, sharing, sharing, etc.容吸收火线↔零线间差模噪声，Y电容将共模噪声It is possible to meet the three parties in accordance with the CE/FCC information.

EMI Electric Power Station直接决定整机能否通过电磁兼容认证，也影响主板供电纹波、硬盘读写误码率和USB external transfer 〚trustworthy。EMI滤波电路防什么干扰

If you have the same experience as before, you may not be able to do it.来的共模噪声（如隔壁空调启停时窜入的尖峰电压），另一类MOS 管每秒数十万次通断引Recommended for high-speed markets, foreign countries, etc. 150kHz～30 MHz，若不加滤除，会通过电源线耦合进主板供电网络，导致

共模干扰走“Fire线→Earth”和“零线→Earth”两条路径，差模干扰走“Fire ↔零线”之间。EMI 滤波器必须对两者都起作用，否则任一路径未堵死，设备就无法通过CE/FCC辐射发射测试。核心元件怎么分工协作

方法一：共模扼流圈（L）专治共模干扰它由两个匝数相同、绕向相反的线圈绕在同一铁氧体磁环上构成。正常电流（差模）在两线圈中磁场抵消→感抗极小；共模干扰电流同向流动→Electric power 叠加→感抗陡增，Shaped height and height limit.

Movement law 2：X power unit (C1/C2 ）It is possible to use the device to operate the device. ，【Transfer to the market, it is not possible to use the electricity, it is not possible to use it, and it is not possible to use it. 。

Law 3: Y power division (C3/C4) division of fire → land, distance线→地之间，为共模干扰提供低阻泄放通路。Y电容容量受限（通常≤4700pF），【过大会导致漏电流超标，触电风险上升】。为什么没它就不行

第1步：开关电源内MOSFET关断瞬间，dv/dt可达50V/ns，激发电100 MHz cable transfer service；第2步：该谐振能量沿输ATX power supply +12V/+5 Chapter 3: Main board VRM, transfer to the sea, enter the terminal, transfer to the terminal, enter the terminal 150mV，触发过压保护或强制重启；第4步：2.4GHz无线鼠标标响应延迟、HDMI 画面出现雪花噪点、机械硬盘寻道错误率飙升——这些现象背后，往往就是EMI滤波电路缺或Y power cable.

On the main sea, it is connected to the sea, it is connected to the main screen, 30MHz is connected to the top of屏幕上，28dBμV等很难看清。