When you disassemble 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 except for the screen touchpad used for display.
So the question is, how did this electronic circuit board come about?
This time, let’s talk about the process of creating this electronic circuit board from scratch.
First of all, you need to know that the electronic circuit board is also called the main board. The main board is generally called PCB (Printed Circuit Board) board, the Chinese name is printed circuit board, which integrates various specifications of resistors, capacitors, inductance diodes, etc., of course, it also contains various Functional IC, under the joint action of these components, the electronic motherboard of electronic products with various functions is obtained.
The electronic motherboard is not created out of thin air, its production is step by step.
The first is the design of the electronic motherboard. The first step in this design is the drawing of the schematic diagram.
It is a diagram of the connection principle between various components on the circuit board. It can be considered that the diagrams that can reflect the circuit principle are all schematic diagrams.
(Figure: schematic diagram of a speedometer)
And in the actual production process, the circuit principles of each module of the electronic motherboard are separated. On the one hand, it is because of the area limitation of the drawing, and on the other hand, because the communication between the modules is connected through the network signal, so as long as the network signal is not If the mark is 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 flow direction of signals or power, and get a glimpse of the core of the circuit board.
At the same time, when designing the schematic diagram, it is necessary to consider the selection of components, including packaging format, withstand voltage value, EMC (electromagnetic compatibility) and other factors, so the selection of components is also a very time-consuming and energy-consuming matter in schematic design. (After the selection is completed, a BOM table is generally produced).
After the schematic diagram, it is necessary to find a way to turn all the components that appear in the schematic diagram into a real PCB board.
So how does this process work?
Then it is necessary to turn each component in the schematic into what it looks like in real life.
At this time, you need to know the concept of packaging - connecting the circuit pins on the silicon chip to the external joints with wires to connect with other devices. Simply put, it is the form of existence of components, such as a 10Ω resistor, which can be packaged into a pin type or a patch type.
Reflected on the component is the specific shape, pin arrangement, and reflected on the PCB board is the spacing, area, quantity and other parameters of the contact points of the pins and wires. It can be concluded that the PCB package is the product of component things mapped onto the PCB.
Then there is the drawing of the PCB board. First, draw a rough mechanical frame, which is the approximate shape and area of the circuit board. Then put the components into the mechanical frame, and generally the same functional modules are placed in adjacent areas.
If there is a specific component library, you can directly select the corresponding component on the schematic diagram, and a corresponding component PCB package position will be automatically generated on the PCB.
However, in the PCB design, the number of layers of the PCB needs to be considered at the beginning. If it is just a simple electronic circuit, generally only one or two layers, top and bottom, are needed. However, if the circuit becomes complicated and the functions increase, it needs Increase the number of PCB layers, including additional power supply layers, ground layers, solder mask layers, etc.
After all the components and components are drawn on the PCB board, the wiring can be done automatically or manually. The wiring is actually what we call the wires, corresponding to the wires 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 the wiring is completed, you can see the preview of the PCB. Of course, if the software supports it, you can also view the 3D rendering, which is the final shape of the circuit board.
After completing all the above processes, only the things designed in the software (PCB diagram) are printed out to the physical circuit board.
This process requires specialized PCB equipment or PCB factories to make proofs according to your design drawings. The effect of proofing is shown in the figure below.
Then solder the corresponding electronic components (resistors, capacitors, ICs, etc.) to the PCB board with solder paste or solder to form the final electronic circuit board.
The above is the whole process of the circuit board from scratch.
[The above information is compiled and released by Aibo Testing. If there is any discrepancy, please correct it in time. If there is any quotation, please indicate the source. Welcome to discuss together. We have been paying attention to its development! Focus: CCC/SRRC/CTA/operator warehousing]