1、 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 open circuit output voltage, that is, the voltage when there is no load and no current output, so it can also be understood that this voltage is the upper limit of the power supply output voltage.
When active voltage stabilizing elements are used inside the power supply, even if the mains voltage fluctuates, its output is also a constant value. For the power supply equipped with small transformers on the market, such as Walkman, if the mains power fluctuates, the output of the power supply will not fluctuate.
Generally speaking, the real no-load voltage of an ordinary power adapter is not necessarily completely consistent with the nominal voltage, because the characteristics of electronic components cannot be completely consistent, so there is a certain error. The smaller the error, the higher the consistency requirements for electronic components, the higher the production cost, so the price is more expensive.
In addition, with regard to the nominal current value, no matter what power supply has a certain internal resistance, 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, and the other is to reduce the output voltage, which is equivalent to internal consumption.
2、 They are all power supplies with the same nominal voltage and different output currents. Can they be used on the same laptop?(power adapter)
The power supply voltage is the same and the output current is different. Can it be used on the same notebook. The basic principle is that the power supply with large nominal current can replace the power supply with small nominal current. It is estimated that some people will think that the power supply with large nominal current will burn out the notebook because the current is large. In fact, how much current depends on the load at the same voltage. When the notebook is running at high load, the current is larger. When the notebook is in standby, the current is smaller. The power supply with large nominal current has sufficient current margin. On the contrary, it is no problem for someone to replace 72W with 56W power supply. The reason is that there is usually a certain margin in the design of power adapter, and the load power is less than the power supply power, so this replacement is feasible in general use, but the remaining power surplus is very small. Once your notebook is connected to many peripherals, such as two USB hard disks, Then the CPU runs at full speed, and there is a base on which an optical drive reads the disk at full speed. In addition, it is estimated that it is dangerous to charge the battery at the same time. Therefore, it is best not to use low current power supply instead of high current power supply.
3.Don't doubt that your power adapter has problems. First look at what your notebook is doing. Do you like the two USB hard disks mentioned above? The CPU is running at full speed. The hard disk is crazy to read and write, and the optical drive is reading the disk at full speed. At the same time, charge the battery, play music loudly, the screen is the brightest, and the wireless network card has been detecting signals. Make good use of power management, It is very important to adjust the working state of the book according to the task.
4、 The nominal voltage of the power supply is much higher than that of my laptop battery. Won't anything happen?(power adapter)
First of all, you should know that the power supply to the notebook is different from the battery to the notebook.
Battery power supply, the output of the battery is pure DC, which is very clean. The battery voltage is neither possible nor need to be designed very high. The chemical characteristics of lithium battery determine that the output voltage of a cell can only be about 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. In fact, it is to protect the battery.
The situation of power supply is more complicated. First, it is necessary to further stabilize and filter the added voltage to ensure stable operation when the power performance is not very good. The stabilized voltage is divided into two parts, one to supply power to the notebook and the other to charge the battery. The part that supplies power to the notebook is the same as that of the battery, The part that charges the battery needs to be added to the cell through the battery charging control circuit. The control circuit can be very complex, so the power supply voltage must be greater than the cell voltage to have sufficient capacity to supply each unit of the charging control circuit. Finally, the voltage really added to the cell will never be the nominal voltage of your power supply. Don't worry.
A suitable power adapter
requires safety certification. A power adapter with safety certification can protect personal safety. To prevent electric shock, fire and other hazards.