Do you know what causes the power adapter to burn out?

The power adapter at home is often burned out when charging. At first, I thought it was because the quality of the power adapter was not good, but I finally checked and found that it was not. So what's the reason?

The first: the output voltage is too high

There will be high output voltage problems, generally all from the regulator sampling and regulator control loop. In DC output, photoelectric coupler, switching power control ic and other power circuits composed of each other's closing control loop, in which all a part of the problem is to cause the output voltage rise.

The second kind: route common fault

Route common faults are very good to know, that is to say, the charger wire will not be connected to the power supply or destroyed, this dismantling cable foundation can solve the problem.

Third: commercial insurance burnt out or destroyed

Key check the rectifier bridge, each diode, switch tube and its large filter capacitance. Cause commercial insurance burning, blackening, will also be the anti-interference power circuit caused by the problem. In particular, special attention is paid to the commercial ignition caused by the thermal breakdown of the switch tube, which will generally burn out the switch power control integrated ic and current detection resistance. Thermistors are also very easy to burn out with commercial insurance.

Fourth: the output voltage is too low

Key reasons for low output:

1. Switch switch power supply load short-circuit fault, especially in the DC/DC converter short-circuit fault or poor performance;

2. The output voltage end filter capacitor or rectifier diode is invalid, which can be resolved according to the alternative method;

3. The characteristics of the switching tube are reduced, resulting in the switching tube can not be all normal on and off, so that the internal resistance of the switching power supply is increased, the load capacity is reduced;

4. Poor switching transformer, not only leads to the output voltage reduction, but also leads to the failure of the switching tube to encourage enough and destroy the switching tube;

Fifth: non-standard power plug

Our standard home installation single-phase electric power plug pole grounding device and vertex and earth two methods, the application of the power plug shown in the diagram should be able to prevent unipolar stabbing, in addition, the appearance of the power plug in China's application of a large number of industrial plug requirements are not detailed, it is very simple to lead to electric shock accident.

Sixth: goods marking is not detailed or not standard

Identification shall include the proper installation, the proper and correct guidance of the customer's key information content to mark the goods, in order to ensure the personal safety of the customer and the security of the industrial chain is one of the fundamental methods.

Seventh: commercial insurance damage

Commercial insurance damage key inspection rectifier bridge, diode, in addition, will be caused by anti-interference power circuit damage. Key check the rectifier bridge, each diode, switch tube large filter capacitance and other positions. Cause commercial insurance burning, blackening, will also be the anti-interference power circuit caused by the problem. In particular, special attention is paid to the commercial ignition caused by the thermal breakdown of the switch tube, which will generally burn out the switch power control integrated ic and current detection resistance. Thermistors are also very easy to burn out with commercial insurance.