What is power adapter?

    The power adapter is a power supply conversion device for small portable electronic equipment and electronic appliances. It is generally composed of shells, transformers, inductors, capacitors, control ICs, PCB boards and other components. Its working principle is to convert AC input to DC output; press the connection. The way can be divided into wall type and desktop type. Widely used in security cameras, set-top boxes, routers, light bars, massagers and other equipment.

product description

    Power adapter, also known as external power supply, is a power supply voltage conversion device for small portable electronic equipment and electronic appliances. It is commonly used in small electronic products such as mobile phones, LCD monitors and notebook computers.

Instructions for use

    There are usually several items on the label of the power adapter that need attention. First, it is the model of the adapter. For example, the model of this adapter is KZ-120100. It tells us several information, that is, its manufacturer, main parameters, etc. The name at the beginning of KZ is generally ##company code, and 120100 means this. The adapter is 12V1A, and the 050200 is 5V2A; the second is the INPUT (input) of the adapter, which is generally AC100-240V~50-60Hz.This shows that the adapter can work normally under the AC voltage of 100V-240V; the third is the OUTPUT (output) of the adapter, DC 12V=1A, which represents the rated voltage of 12V DC, and the maximum current is 1A. Two numbers can quickly calculate the wattage of the adapter. For example, for this adapter, the voltage is 12V*current 1A=12W (power), indicating that the power supply is a 12W adapter.
    Most laptop power adapters are suitable for 100~240V AC (50/60Hz). Basically, most laptops have an external power supply and use a power cord to connect with the host, which can reduce the size and weight of the host. Only a few models have the power supply built into the host.
    There is a nameplate on the power adapter, which indicates the power, input and output voltage and current, etc., pay special attention to the range of the input voltage, this is the so-called "travel power adapter", if you go to a country where the mains voltage is only 110V This feature is very useful. Some parallel notebook computers are only sold in the country of origin. There is no such compatible voltage design, or even a single input voltage of 110V, which will burn when plugged in under the 220V mains voltage in my country.

Precautions

一. What does the nominal voltage and current of the power adapter (hereinafter referred to as the power supply) mean? First of all, the nominal voltage of the general power supply refers to the voltage of the open-circuit output, that is, the voltage when no load is connected to the outside and there is no current output. Therefore, it can also be understood that this voltage is the upper limit of the output voltage of the power supply.
In the case of the use of active voltage regulator components inside the power supply, even if the mains voltage fluctuates, the output is a constant value. Like small transformers on the market, such as the power supply equipped with Walkman, if the mains voltage fluctuates, The output of the power supply will not fluctuate accordingly.
Generally speaking, the real no-load voltage of ordinary power adapters is not necessarily exactly the same as the nominal voltage. Because the characteristics of electronic components cannot be completely consistent, there is a certain error. The smaller the error, the higher the consistency requirements for electronic components. , the production cost is high, so the price is also more expensive.
    In addition, regarding the nominal current value, any power supply has a certain internal resistance, so when the power supply outputs current, a voltage drop will be generated internally, resulting in two things, one is to generate heat, so the power supply will be hot, the other One is to cause the output voltage to drop, which is equivalent to internal consumption.

二. All power supplies with the same nominal voltage have different output currents. Can they be used on the same laptop?
The power supply voltage is the same, the output current is different, can it be used on the same notebook. The basic principle is that a power supply with a large nominal current can replace a power supply with a small nominal current. It is estimated that some people will think this way, thinking that a power supply with a large nominal current will burn out the notebook because the current is too large. How much current actually depends on the load for the same voltage. When the books are running at high load, the current is larger, and when the books are in standby, the current is smaller, and the power supply with a large nominal current has sufficient current margin. On the other hand, there is no problem with using a 56w power supply instead of a 72w power supply. The reason is that the design of the power adapter usually leaves a certain margin, and the load power is smaller than the power supply power, so this kind of replacement is feasible in general use. But the remaining power margin is very small. Once your notebook is connected to a lot of peripherals, such as two usb hard drives, then the cpu runs at full speed, and there is a base with an optical drive on it to read the disk at full speed, plus at the same time Charging the battery can be dangerous. Therefore, it is best not to replace the high-current power supply with a low-current power supply.

三. The same machine, others' power supply temperature is very low, mine is always very hot, why?
Don't suspect that there is a problem with your power supply, first look at what your notebook is doing, whether it is like the two USB hard drives mentioned above, the CPU runs at full speed, the hard drive reads and writes frantically, the optical drive reads the disk at full speed, while charging the battery, playing loudly It is very important to make good use of power management and reasonably adjust the working state of the notebook according to the task.

四. The nominal voltage of the power supply is much higher than the voltage of my laptop battery. Will it not happen?
First of all, you need to know that the power supply to the notebook is different from the battery power supply to the notebook.
    Battery powered, the output of the battery is pure DC, which is very clean. The voltage of the battery is neither possible nor required to be designed to be very high. The chemical characteristics of the lithium battery determine that the output voltage of a cell can only be around 3.6V, so Many batteries use three-stage series connection, and 10.8V has become a very popular battery voltage. The nominal value of some batteries is slightly larger than the integer multiple of 3.6V, such as 3.7V or 11.2V, etc., in fact, to protect the battery.

     Power supply, the situation is a little more complicated. First of all, it is necessary to further stabilize and filter the added voltage to ensure stable operation under the condition of poor power supply performance. The other way is to charge the battery. The part that supplies power to the notebook is the same as when the battery is powered, and the part that charges the battery needs to be added to the cell through the battery’s charging control circuit. The control circuit can be very complicated, so the power supply voltage It must be greater than the cell voltage to have sufficient capacity to supply each unit of the charging control circuit. The final voltage added to the cell will never be the nominal voltage of your power supply. Don't worry.
    A suitable power adapter is required to have safety certification, and a power adapter with safety certification can protect personal safety. To prevent electric shock, fire and other hazards.

use

    Switching power supply products are widely used in industrial automation control, military equipment, scientific research equipment, LED lighting, industrial control equipment, communication equipment, power equipment, instrumentation, medical equipment, semiconductor refrigeration and heating, air purifiers, electronic refrigerators, liquid crystal displays, LEDs Lighting, communication equipment, audio-visual products, security, computer cases, digital products and instruments and other fields.