What are the functions of the Y capacitor in the charger

Mobile phone chargers have become one of the commonly used items in our daily lives. If we encounter a low-quality charger, it not only harms the battery but also harms ourselves. Due to poor quality of accessories or electrical performance issues, it is easy to experience faults such as short circuits, overheating, and burning. This can cause users to lose their chargers, and can even lead to various hazards.

I believe everyone has heard of the Y capacitor in chargers. The Y capacitor is used for common mode filtering and is connected between L and ground or N and ground to filter out common mode signals from L to ground or N to ground. The Y capacitor is usually used symmetrically and mainly serves as a bypass; Decoupling; Filtering; Energy storage.

The Y capacitor of the mobile phone charger is used for common mode filtering, and in principle, the larger the capacity, the better. But in reality, the larger the capacity, the greater the leakage current, and the Y capacitor is connected to AC resistance DC. So when we charge our phones, we should choose a high-quality charger, and the quality of the Y capacitor will also affect the quality of the charger.