Take you through a circuit board, from design to production (dry goods)

Open the inside of the mobile phone , You will find that the main part of the mobile phone is an electronic circuit board with various components in addition to the screen touch board for display .

So here's the question , How did this electronic circuit board come from ？

This time, let's talk about the process of the electronic circuit board from scratch .

The first thing you need to know is , Electronic circuit board is also called motherboard , The motherboard is generally called PCB（Printed Circuit Board） plate , Chinese Name: printed circuit board , All kinds of resistors are integrated on it , capacitance , Inductive diode, etc , Of course, it also contains various functions IC, Under the combined action of these elements , The electronic motherboard of electronic products with various functions is obtained .

Electronic motherboards are not created out of thin air , Its production comes step by step .

The first is the design of electronic motherboard , The first step of this design is to draw the schematic diagram .

It is a diagram of the connection principle between various components on the circuit board , It can be considered that all the diagrams that can reflect the circuit principle are schematic diagrams .

（ chart ： Schematic diagram of a tachometer ）

And in the actual production process , The circuit principle of each module of the electronic motherboard is separate , On the one hand, it is because of the area limitation of the drawing , On the other hand, it is also because the communication between various modules is connected through network signals , So as long as the network signal is not marked wrong , There will be no confusion in the schematic diagram .

With the schematic diagram, you can know the working principle of each module in the circuit board and the signal or power The flow of , Take a look at the core of the circuit board .

At the same time, when designing the schematic diagram , The selection of components should be considered , Including encapsulation format , Withstand voltage value ,EMC（ Electromagnetic compatibility ） And so on , Therefore, the selection of components is also a very time-consuming and energy-consuming thing in schematic design （ After model selection, one will be made BOM surface ）.

After the schematic , You need to find a way to turn all the components in the schematic into a real piece PCB plate .

So how does this process work ？

Then you need to turn the components in the schematic into real life .

At this time, you need to know the concept of encapsulation —— Put the circuit pins on the silicon chip , Lead the wire to the external connector , To connect with other devices . Simply put, it is the existence form of components , For example, a 10Ω The resistance of , It can be packaged into pin type , It can also be packaged into a patch type .

The specific shape reflected on the components , Pin layout , And reflect on PCB On the board is the distance between the contact points of pin wires , area , Quantity and other parameters . It can be summarized as PCB Encapsulation is the mapping of component things to PCB The product of .

Then is PCB Drawing of slab , First draw a rough mechanical outline , That is, the approximate shape and area of the circuit board . Then put the components into the mechanical frame , Generally, the same functional modules are placed in adjacent areas .

If there is a specific catalog , You can directly select the corresponding components on the schematic diagram , stay PCB A corresponding component is automatically generated on the board PCB Package location .

But in the PCB At the beginning of the design, it is also necessary to consider PCB The number of layers , If it's just a simple electronic circuit , Generally, only one or two layers are required ,top and bottom, But if the circuit becomes complicated , Function added , It needs to be increased PCB The number of layers , Include additional power layers , Ground plane , Solder mask, etc .

All components PCB After the drawing is finished , You can perform the action of wiring , It can automatically route , It can also be wired manually , Wiring is actually what we call a wire , Corresponding to the wire on the schematic diagram , Of course , In the actual production process , The position of the wire should be adjusted according to the specific situation .

After wiring , You can see that PCB Preview of , Of course , If supported by the software, you can also view 3D design sketch , That is, the final circuit board will be shaped .

After completing all the above processes , There are only things designed in the software （PCB chart ） Give it a physical printed circuit board .

This process requires special PCB Equipment or PCB The factory proofs according to your design drawings , The effect of proofing is shown in the following figure .

Then put the corresponding electronic components （ resistance , capacitance ,IC etc. ） Solder to with solder paste or solder PCB The final electronic circuit board is formed on the board .

The above is the whole process of the circuit board from scratch .