What is a power adapter? The power adapter, also known as the external power supply, is the power supply voltage conversion device for small portable electronic devices and electronic appliances. Its function is to convert the high voltage of 220 volts in the home to the stable low voltage of about 5 volts to 20 volts that these electronic products can work, so that they can work normally. It is also the power supply transformation equipment for small portable electronic equipment and electronic appliances. It is generally composed of shell, power transformer and rectifier circuit. According to its output type, it can be divided into AC output type and DC output type. According to the connection mode can be divided into wall type and desktop type. The following is a detailed look at the power adapter classification and advantages and disadvantages.
There are two main types of power adapters: linear power supply and switching power supply.
1, linear power supply is the alternating current through the transformer transformer, rectifier circuit rectifier filter rectifier to get unstable DC voltage, power adapter to achieve high precision DC voltage, must be through the voltage feedback circuit to adjust the output voltage. Advantages: Mature power supply technology, simple circuit, and no switching power supply interference and noise. Disadvantages: The voltage feedback circuit works in a linear state, the power consumption of the regulating tube is high, the conversion efficiency is low, and the equipment is heavy due to the use of inductive transformer.
2. Switching power supply is a kind of power supply that USES modern electronic technology to control the time ratio of switching on and off and maintain stable output voltage. The switching power supply of power adapter is generally composed of pulse width modulation (PWM) control IC and MOSFET. Disadvantages: large interference to the power circuit, trouble when maintenance is more difficult.
Two, enough to confirm that the power adapter is a transformer and rectifier.
So the adapter is a transformer, and we should all know that ac 220V changes voltage through the transformer, and dc through the rectifier, there is consumption, and these consumption will be converted into heat, so it is normal for the power adapter to heat. The transformer is made of silicon steel. After the transformer is electrified, the magnetic flux will be generated. The magnetic flux will lead to a force action between the silicon steel plates, thus producing a buzzing sound, which is normal. But fire and earth sounds are not normal for many reasons:
Ac voltage is unstable.
2. Chip damage.
3. Short circuit between turns.
4. Component damage.
Application of power adapter
Widely used in consumer electronics, most of which provide output power of less than 100 watts, demand is growing rapidly. These include e-bike battery chargers, small LCD televisions, laptops, printers, DVD players and set-top boxes. Most early power adapters used linear transformers. With the high efficiency and wide input voltage range of power adapters required by consumer electronics, as well as the increase of copper, iron and labor costs, the original linear transformers in these power adapters were gradually replaced by switching power supply.
It is not difficult to distinguish the advantages and disadvantages of the two. The main volume, weight, output voltage range. Transformer type, reducing voltage through the coil, after stage rectification, stabilizing voltage, large volume, stable performance, shortcomings of high cost transformer, easy to heat. The switch is small in size and low in cost, but it is easy to be damaged if the components are of poor quality. The main difference is in volume and weight.
How to use power adapter scientifically?
Note whether the temperature of the power adapter is reasonable
As we all know, as long as the power adapter is used, it will generate heat, and this heat will affect the normal use, of course, for the service life of the adapter will also have a great impact. But we shouldn't stop using it just because it generates heat and affects its normal performance. Therefore, we should start from the daily use of science to pay attention to the temperature is reasonable.
For example, when using it, try to avoid the direct sunlight, so as to avoid its temperature suddenly too high. Of course, like some easy to burn and explosive, such as the source of fire is also from the farther the better. Because the use of the power adapter will cause heat, so remind everyone to pay attention to turn off the power switch when charging is completed, so as to make it completely stop working, in order to better extend the service life of the adapter.
Second, master the use frequency of power adapter
Many people have such an experience, that is a lot of electrical appliances if not used for a long time, then naturally there will be a lot of faults. The same is true of adapters. If you don't use them for too long, the moisture in the air will accumulate to a certain amount, and then it will enter the interior. So if not used for a long time and suddenly want to use, it is very easy to cause short circuit or even can not use the phenomenon.
So how do you avoid or reduce it? How long does not use affect the service life of the power adapter? The trick is to let the adaptor run for a while if you don't think you'll be using it for a long time. This will generate enough heat to evaporate some of the water inside the adaptor.
Power adapter for daily use
1. Be careful not to insert the power cord port into other ports, horizontally insert and unplug the cord to prevent the port from becoming loose. Do not plug or unplug serial ports, parallel ports, PS/2 and other interfaces with live power.
2. Check the capacitance, resistance and inductance for any problem. If the capacitance is bulging, it is best to replace it in time to avoid hidden danger. Pay attention to the power cord. When winding the laptop power cord, try to be careful not to break the internal cable and form a disconnect. If the external power supply does not supply, you can try to plug in the laptop battery. If the laptop starts up properly, there may be a problem with the laptop's power cord or the laptop's power adapter. Then test with a multimeter to find out if there is a problem with the laptop's power cord, to simplify troubleshooting and not try to open the laptop's power adapter case in the first place.
3, the shell to avoid scratch, collision shell. Use a professional computer bag. Do not push the laptop on the desktop to prevent the floor MATS from falling off.
4. If the original notebook power adapter has problems and cannot be repaired, you can use other adapters to replace it first, as long as the output voltage and current are equal to the interface. Still have is to do not destroy casing as far as possible, after casing is destroyed, can appear electromagnetic radiation strengthens wait for a problem, affect the stability of notebook. It is also very harmful to one's own body. If the casing breaks, try to send it for repair. After opening the appearance and shielding layer, it is better to first check the solder foot, visual observation can be, the circuit intermittently, generally is bad contact.
5, for the OPTICAL drive, do not touch the internal components of the OPTICAL drive, the use of high quality disc, improve the life of the optical drive, loading and unloading discs, to hold the tray with your hands.
6. The power adapter should not squeeze the power adapter cable, which may lead to rupture of the external insulator of the power cord. Do not damage the power cable due to long-term load bearing. You also want to prevent falls and collisions. Disconnect the power adapter from the socket when the computer is not in use.
Above for everyone about the power adapter knowledge, I hope you can carefully understand more about the power adapter.