How to choose a power adapter? Remember these 9 basic principles! The power adapter is the adapter between the mains and the power supply to be charged. For example, a 5V/1A power adapter is equipped for charging a mobile phone.
Ⅰ. The power adapter can only be matched with a large size
For example, the charging current needs 5V/800mA and the best power adapter should be 5V/1000mA (5V/1A).
If the power adapter is too small, it may cause the voltage to be lowered during charging, causing the sampling value of the charging circuit to drift. What is sampling drift? Everyone should know that the charging of lithium battery chargers must be limited voltage and constant current. The most basic reference values of voltage limiting and constant current need to be valued in the circuit. The value of the battery charger current is generally obtained by calculating the voltage across the current sampling resistor. The key point of constant current is to protect the battery plate and avoid the impact of high current on the battery plate. Lithium battery chargers can quickly charge lithium batteries and can be several times larger than this value. Generally speaking, as long as the voltage is stable, even if the current fluctuates, the damage to the lithium battery is generally not large. In simple terms, a certain range of current fluctuations is "relatively safe" for lithium batteries.
Ⅱ. Choose a power adapter with good quality
What is a good quality power adapter? For the power adapter, electromagnetic compatibility, output ripple and voltage fluctuation are all very important indicators. Ordinary consumers can't know which manufacturer is the best. The only thing we can trust is the manufacturer, so rejecting copycats is a slogan that will never change!
Ⅲ. Whether is the power adapter the bigger the better
Strictly speaking, the power adapter is fine as long as it is slightly larger than required. Assuming that your charged circuit is very efficient and stable, the influence of high-power adapters can theoretically be ignored. That is, no matter how large the input power is, there will be no problem. But you have to admit that the machine is a man-made thing. Nobody can guarantee that the things he made are perfect. In case the charging circuit breaks down and the input terminal is instantly added to both ends of the lithium battery, nobody can foresee the consequences. In general, the adapter should only be slightly larger than the requirements. If the adapter is too large, it can only be used temporarily and cannot be used for a long time.
Ⅳ. Power adapter voltage selection
Strictly speaking, the voltage of the power adapter cannot have an error greater than 1%.
Whether the output voltage of the power adapter is too high or too low, it can cause devastating consequences. It is most important to choose the power adapter provided by the original factory. Each manufacturer has identification and protection measures for their own lithium battery products. In fact, we can't blame the manufacturers for not considering the free choice of consumers. If the manufacturer does not take strict protection measures for such dangerous products as lithium batteries, it is believed that the word explosion of lithium batteries will often appear in the news headlines.
Ⅴ. What is the power adapter input charging identification
The manufacturer's requirement is one battery (battery) with one charge (power adapter). That is, my power adapter can only adapt to my lithium battery charging circuit. When consumers choose a power adapter other than the original factory, the circuit will automatically turn off the charging. Here is to prevent ordinary consumers from abusing substandard power adapters. Some mobile power supplies can be adapted to a variety of mobile phones because they have a circuit to switch the two wires to meet the requirements of various mobile phones. More adaptation means more problems. The product can be easily adapted to other people's circuits.
Ⅵ. How to choose a power adapter with good quality and good price
In response to the above, add the following nine basic principles for choosing a power adapter:
1. High-end electrical equipment should use a power adapter with protection function.
2. Do not mix a power adapter with ordinary electrical appliances for high-end electrical appliances.
3. Do not use multiple electrical appliances whose accumulated power exceeds the rated power of the adapter on the same socket.
4. Equipment with a grounding pole adapter should use a three-pole socket with grounding to ensure that the grounding wire is unobstructed.
5. When using electrical appliances, it is best to insert the adapter first and then turn on the power switch. After use, it is best to turn off the switch and then unplug it.
6. Do not plug and unplug the power adapter frequently. Use switches whenever possible. If it is not used for a long time, the power should be cut off and put away properly.
7. Do not use the power adapter and electrical appliances in a humid environment for a long time.
8. If the electrical appliance has requirements to prevent electric shock, it is recommended to use a power adapter with leakage protection function.
9. If the protection door is not closed during use, you should cut off the power supply, repeat the plug and pull action to restore it.