The circuit board can be called a printed circuit board or a printed circuit board. A kind of highly reliable and excellent flexible printed circuit board made of material. It has the characteristics of high wiring density, light weight, thin thickness and good bending property), soft and hard combination board (reechas, SoftandhardcombinaTlonplate) -The birth and development of FPC and PCB gave birth to the new product of soft and hard board.
Therefore, the soft and hard combination board is a flexible circuit board and a rigid circuit board. After pressing and other processes, it is combined according to the relevant process requirements to form a circuit board with FPC characteristics and PCB characteristics.
Why is the circuit board green
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The green part is called solder resist, and its components are resin and pigment. The green part is green pigment, and there are various other colors, which are no different from decoration paint. The assembly soldering is fertile and flowable before it is printed on the circuit board. After printing on the circuit board, it must be "cured" at the end, allowing the resin to be cured and hardened by heat. The purpose of the solder mask is to protect the circuit board from moisture, oxidation and dust. The only place not covered by the solder mask is usually the pad, which is used for solder paste.
Generally, we choose green, because green is less irritating to the eyes, and the production and maintenance personnel are not prone to eye fatigue when they are staring at the PCB board for a long time. Commonly used colors are yellow, black and red. All kinds of colors are paints sprayed on the surface after manufacture.
There is another reason, because the commonly used color is green, so the factory has the most green paint in reserve, so the cost of oil is relatively low. And because when repairing the PCB board, it is easier to distinguish the difference between different wiring and white, while black and white are relatively difficult to see. In order to distinguish their own product grades, each factory uses two colors to distinguish high-end series and low-end series. For example, Asustek, a company that makes computer motherboards, yellow boards are low-end, and black boards are high-end. Biostar's rebounds are high-end, and green boards are low-end.
Component introduction diagram on the circuit board
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1. There are signs on the circuit board that the beginning of R is the resistor, the beginning of J is the inductance coil (usually the coil is wound on the iron core ring, and some have a closed shell) and the beginning of C is the capacitor (tall and cylindrical, covered with plastic The ones with cross marks on them are electrolytic capacitors and the flat ones are chip capacitors), the other two legs are diodes, the three legs are triodes, and the many legs are integrated circuits.
2. Thyristor rectifier UR; control circuit rectifier VC with power supply; frequency converter UF; converter UC; inverter UI; motor M asynchronous motor MA; synchronous motor MS; DC motor MD; wound rotor induction motor MW ; Squirrel cage motor MC; Electric valve YM; Solenoid valve YV and so on.
3. Extended reading Attached is part of the component name marking information on the motherboard circuit board with diagrams.
