Power adapter structure

　　If someone mentioned a power adapter to you suddenly, you might wonder what a power adapter is, but you might not have thought that it is in a corner around you that you have almost forgotten, and there are countless products that match it, such as the more commonly used ones. Notebook computers, security cameras, repeaters, set-top boxes, IT products, toys, audio, lighting, and other equipment, its function is to convert the high voltage of 220 volts at home into a stable low voltage of about 5V~20V that these electronic products can run Voltage, today I will introduce to my friends what a power adapter is.

　　The usual power adapters are composed of shells, high frequency transformers, wires, PCB circuit boards, hardware, inductors, capacitors, control ICs and other components, as follows:

　　1. Varistor, its function is that when the external current and voltage are too high, the resistance of the varistor will quickly become very small, and the fuse connected in series with the varistor will be blown, thus protecting other power circuits from being burned.

　　2. The fuse, the specification is 2.5a/250v, when the current in the power circuit is too large, the fuse will blow to protect other components.

　　3. Inductance coil (also called choke coil), the main function is to reduce electromagnetic interference.

　　4. The rectifier bridge, the specification is d3sb, is used to convert 220v alternating current into direct current.

　　5. The filter capacitor, the specification is 180uf/400v, filters out the AC ripple in the DC power, and makes the power circuit more reliable.

　　6. Operational amplifier ic (integrated circuit), an important part of protection power circuit and current and voltage regulation.

　　7. The temperature probe is used to detect the internal temperature of the power adapter. When the temperature is higher than a certain set value (different brands of power adapters have slightly different temperature thresholds), the protection power circuit will cut off the adapter. Current and voltage output, so protect the adapter from damage.

　　8. The high-power switch tube is one of the key components in the power adapter. The power adapter can operate "one on and one off", and the switch tube is indispensable.https://powerstation-gf.com/prodcuts/SPS-001-wall-mounted-home-energy-storage_283.html

　　9. Switching transformer, one of the key components in power adapter.

　　10. The secondary rectifier tube converts low-voltage alternating current into low-voltage direct current. In ibm's power adapter, the rectifier is usually operated in parallel by two high-power, in order to obtain a relatively large current output.

　　11. The secondary filter capacitor, the specification is 820uf/25v, there are 2 in total, which can filter out the ripple in the low-voltage direct current. In addition to the above components, there are adjustable potentiometers and other resistance-capacitance components on the circuit board.

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