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What are the factors that affect the adapter voltage?
What are the factors that affect the voltage of a power adapter?
1, switching power supply load short circuit fault (especially short circuit or poor performance, etc.) DC/DC converter, at this point, first disconnect all the load switch power supply circuit, checking is switching power supply circuit failure or malfunction with the load circuit. If the load circuit is disconnected and the voltage output is normal, it indicates that the load is too heavy; Or the switch power circuit is faulty.
2, the output voltage end filter capacitor or rectifier diode failure, can be judged by the replacement method.
3, the performance of the switch tube is reduced, resulting in the switch tube can not be normally switched on, so that the internal resistance of the power supply increases, the load capacity decreases.
4, the switch transformer is bad, not only causes the output voltage drop, but also causes the switch tube excitation shortage, thus damaging the switch tube.
Poor 5, 300 v filter capacitance, the power load ability is poor, a load output voltage will drop.
Output overvoltage
The overvoltage usually comes from the stabilized voltage sampling and stabilized voltage control circuit. In DC output, sampling resistance, error sampling amplifier such as TL431, optocoupler, power control chip and other circuits composed of closed control loop, any part of the problem will cause the output voltage rise.
Fuse normal, no output voltage
The safety tube is normal and no output voltage indicates that the switching power supply is not working or has entered the protection state. The first step is to check the value of the starting voltage of the starting pin of the power control chip. If there is no starting voltage or the starting voltage is too low, check whether the components connected to the starting pin and the starting resistance leak electricity.
If the power control chip is normal, the fault can be quickly detected through the above monitoring. If there is a starting voltage, the output end of the control chip shall be measured to see whether there is a jump in high or low level at the moment of starting up. If there is no jump, it indicates that the control chip is damaged, the peripheral oscillating circuit element is damaged or the protection circuit is faulty. By replacing the control chip and checking peripheral components, check one by one. If in jump, most cases for the switch tube is bad or damaged.
The safety burns out or explodes
Mainly check the rectifier bridge, each diode, switch tube and 300 volts on the large filter capacitor. Cause insurance burning, black, also may be anti-interference circuit caused this problem. In particular, it is worth noting that the breakdown of the switch tube leads to ignition, which usually burns out the power control chip and current detection resistor. Thermistors can also easily be burned out along with the safety.
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How to extend the service life of power adapter
Cold and heat protection. Do not place the charger in a place with too high temperature. High temperatures can shorten the life of electronic devices, damage chargers, and warp or melt certain plastic parts. Do not store the charger in a cold place. If the charger is working in an extremely cold environment, the increased internal temperature can cause moisture inside the charger and damage the circuit board.The service life of electronic products directly affects the cost performance of electronic products, so what do we need to pay attention to in the process of use? 1. Release static electricity during cleaning. Clean power adapters and charging ports regularly. Use wet cloth or ESD cloth, do not use dry cloth. 2. Waterproof and moisture-proof. As an electronic product, the corrosion and oxidation degree of the internal electronic components will vary if they are accidentally exposed to water or humid air when not used for a long time. 3. Anti-fall and anti-vibration. Mobile phone chargers are actually fragile parts, the internal parts can not withstand impact. Especially to prevent accidental landings during use. Do not throw, hit or shake the charger. Rough handling of the charger can damage the internal circuit board. 4. Cold and hot protection. Do not place the charger in a place with too high temperature. High temperatures can shorten the life of electronic devices, damage chargers, and warp or melt certain plastic parts. Do not store the charger in a cold place. If the charger is working in an extremely cold environment, the increased internal temperature can cause moisture inside the charger and damage the circuit board. 5. Resistance to effective chemicals. Do not use harsh chemicals, cleaners or strong cleaners to clean the charger. To clean the outside of the charger, wipe with cotton dampened with a small amount of anhydrous alcohol.
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Check whether there is any problem on capacitance resistance inductance, such as the capacitance in bulge, had better change in time, lest leave hidden trouble. Pay attention to the power cord. When winding the power cord of the notebook, try to pay attention to avoid breaking the internal cable to form a break. If the external power supply does not power, then you can plug in the laptop battery to try, if the laptop can start normally, there may be a laptop power cord or laptop power adapter problem. Then test with a multimeter to find out if there is a problem with the laptop power cord, in order to simplify the difficulty of troubleshooting, do not try to open the laptop power adapter housing at first.
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Does wireless charger have radiation to affect person?
Both are within safe limits, and the magnetic field generated by the charger is weak enough to charge the device without affecting nearby credit cards, video tapes and other magnetically recorded objects. However, try to avoid direct contact with the charging platform while charging.
2023-04-04