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What should I pay attention to when buying charger?
Nowadays, more and more digital products have entered our life, such as notebook computer, mobiles phones, PSP, etc., which enrich our life. But these digital products often bring us some trouble, that is to say, they all need to be charged, and the chargers of many digital devices are special. If the charger is damaged or lost, it is sometimes difficult to buy the original charger, so we have to buy some replacement products. At this time, the charger interface type, output voltage and current become the three key factors we must consider when purchasing.
Charger
1. Interface: there must be the same interface, or you can connect the corresponding converter interface, but this is a bit redundant.
2. Output voltage: it is better to have the same output voltage. If there is no accurate one, the difference between the output voltage and the original charger is less than 5%, which is basically no problem. However, if the difference between the two output voltages is too large, the device will not be able to charge, start or even burn out.
3. Current: many people think that the current should be exactly the same, otherwise too much current will flow into our digital equipment and cause damage to the digital equipment. In fact, this kind of understanding is wrong, we can explain this problem according to what we have learned in physics.
According to Ohm's law, in the same circuit, the current in the conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor, I = u / R.. When the voltage is constant, the current on the line depends on the resistance of the load, that is, the digital device itself determines the current of the line, not the maximum output current of the charger itself.