How to repair the power adapter
Due to the compact structure, large power consumption and high heat generation, notebook computer power adapters have become relatively high failure rates. After these power adapters are damaged, it usually costs tens to hundreds of yuan to buy an original one on the market. For beginners, these power adapters with switching power supply seem to be quite complicated and difficult to maintain.However, the internal circuit design of power adapters for laptops of different brands and models is roughly the same. The working principle is actually not difficult to repair.
1. Tool preparation In fact, the laptop power adapter is not a high-tech product. In fact, the principle of power adapters such as mobile phones and digital cameras is basically the same. As long as people who know some electronic knowledge can repair it. Therefore, we only need multimeters, screwdrivers, welding tools, etc. (see Figure 1).
2. If the external power supply does not supply power during the disassembly process, you can plug in the battery and try. If the machine can start normally, there may be a problem with the power cord or adapter. Then test with a multimeter to find out if there is a problem with the power cord to simplify maintenance. Do not try to open the adapter case at the beginning.
3. To find the fault, first check the solder feet with the naked eye, and then check the circuit with a multimeter. If the circuit is intermittent, the contact is generally poor. Check the capacitors, resistors, and inductors for any problems. If the capacitors bulge, it is best to replace them in time to avoid hidden dangers. Use a multimeter to test the protection circuit and rectifier circuit. Figure 6 is the protection circuit. The rectifier circuit is a filter circuit composed of an inductor and a capacitor, and then enters a switch tube circuit composed of a transistor (see Figure 7).
4.Finally, in addition to the usual maintenance, when buying a laptop or purchasing a power adapter separately, you need to pay attention to the quality of the power adapter. Never buy a sub-charged product. The strong quality and kindness to use will be A very good ending. As for the maintenance of the power adapter, you can usually read more information in these areas. If your electronics level is limited, especially when soldering the circuit, you may ask a knowledgeable friend to help. Of course, during the early warranty period, it is best to send in repair s Choice.
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|| Release time: 2019.12.17 Source:|
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Dongguan Qiqi Industrial Co., Ltd. specializes in producing: power adapters , chargers, LED drive power supplies, car chargers, switching power supplies, etc ...