What is the power adapter?

　　Power adapter is a power supply conversion device for small portable electronic equipment and electronic appliances. It is generally composed of a casing, a power transformer and a rectifier circuit. According to its output type, it can be divided into AC output type and DC output type; The connection method can be divided into wall type and desktop type. It is widely used in equipment such as mobile phone handsets, game consoles, language repeaters, walkmans, notebook computers, and cellular phones.

The role of the power adapter:

　　 Generally speaking, power adapters are transformers and rectifiers whose function is to convert alternating current into direct current electronic products. Home AC power is 220v, and our computer uses DC 12v (as if it is), so we can be sure that the power adapter is a transformer and rectifier. The power adapter is a transformer, so we should all know that AC 220v is transformed into a voltage through a transformer and transformed into a direct current through a rectifier. There is consumption here, and these consumption will be converted into heat, so it is normal for the power adapter to generate heat. The transformer is made of silicon steel sheets. After the transformer is energized, magnetic flux is generated. The magnetic flux will cause the silicon steel sheets to generate force and generate a buzzing sound. This is normal. However, the sound of the ground is abnormal due to many reasons: 1. The AC voltage is unstable. 2. The chip is damaged. 3. Short circuit between turns. 4. The components are damaged and so on.

Can the power adapter be universal?

　　 Suddenly the laptop battery is running low on some occasions and there is no power adapter. This situation is very anxious and embarrassing. Some friends may try to borrow other's laptop power adapter, but everyone should be aware that products of different power adapter brands cannot be used universally.

There are three main reasons:

1. Interfaces are different: Most laptop power adapter brands have different interfaces. Different interfaces are relatively safe, because at least you will not insert a power adapter that does not match the current or voltage to power the laptop, which may cause computer hardware damage .

2. Different voltages: different brands of laptop power adapter voltages are different. Even if the power adapter interface is the same, it is not possible to use different brands of laptop power adapters for power supply.

3. The current is different: the current of the power adapter of different brands of notebook computers is also different. Even if the power adapter is used between laptops of the same brand, it is necessary to confirm the voltage and current specifications.

Optional power adapter

　　 When purchasing a power adapter, you should pay attention to the following aspects:

1. The logo is clear and the information is complete. The mark is an important information that instructs the user to install and use it correctly, and is the most basic content to ensure the user's personal and property safety. At least the following information should be included: the name, trademark or identification mark of the manufacturer or distributor; the model code or model specification; the nature of the power supply; the rated power supply voltage range; the output voltage range, etc.

2. Pay attention to the rated power supply voltage range. Because the mains voltage in our country is 220V, when purchasing the adapter, the rated power supply voltage (that is, the input voltage) range should include 220V, otherwise the adapter will not only not work normally, but may also bring unsafe hazards such as burnout, breakdown and short circuit.

3. Pay attention to the nature of the output voltage. The output of the power adapter has two types: AC and DC. When purchasing, select the voltage type that meets the needs of the intended use. On the power adapter logo, the symbol of the AC logo is “～”, and the symbol of the DC logo is “—”. If you choose an adapter whose output is DC, you should also consider the consistency of the positive and negative polarities of the output terminals with the equipment requirements.

4. Pay attention to the output current and voltage range. The output current and voltage are an important index for selecting an adapter, and should match the current and voltage required by the electronic and electrical products that need to be supplied with power. If the voltage and current are too high, the electronic and electrical products will be damaged. If the voltage and current are too low, the equipment will not work normally or overload work, which will affect the safety performance.

5. Whether there is a safety certification mark. From design to mass production, power adapter products need to go through a series of tests to verify whether they meet safety requirements. Products that have passed the safety certification test stipulated by our country will be affixed with the "CCC" mark when they are sold.