Generally speaking, the effect of power adapter is transformer and rectifier. Household AC is 220V, while my computer uses DC 12V. It seems that so, it is certain that the power adapter is a transformer and rectifier. The transformer will generate heat, so I know that the transformer will generate heat through the DC adapter, so it will also consume heat through the transformer.
The transformer is made of silicon steel sheet. After the transformer is powered on, magnetic flux will be generated. The magnetic flux will cause the force effect between silicon steel sheets, resulting in buzzing sound. This is normal, but the earth sound is abnormal when it is too hot. There are many reasons: 1. The AC voltage is unstable. 2. The chip is damaged. 3 turn to turn short circuit. 4. Component damage, etc. By the way, the effect of the adapter is an electronic product that converts alternating current into direct current.
Power adapters with large space are generally built-in. Generally, the size of the adapter is not small. Machines with small volume are external. In order to save space, it is also convenient to replace. The adapter uses mains power, and the voltage is relatively high, so it is risky to put it inside the machine.
