PCB Tech - Rigid-flex board factory PCB placement and connection

The PCB design of the rigid-flex board factory seems to be complicated. It is necessary to consider the direction of various signals and the transmission of energy. The distress caused by interference and heat is always accompanied. But in fact, the summary is very clear, and you can start from two aspects: to put it bluntly: "how to put it" and "how to connect".

1. Follow the layout principle of "big first, then small, difficult first, easy first", that is, important unit circuits and core components should be laid out first. This is the same as eating a buffet: buffets have a limited appetite and pick the ones you like first, and when PCB space is limited, pick the important ones first.

2. The principle block diagram should be referred to in the layout, and the main components should be arranged according to the main signal flow of the board. The layout should meet the following requirements as much as possible: the total wiring should be as short as possible, and the key signal line should be the shortest; the layout of the decoupling capacitor should be as close as possible to the power supply pin of the IC, and the loop formed between it and the power supply and ground should be the shortest; reduce the signal Run unjustly to prevent accidents on the road.

3. The arrangement of components should be convenient for debugging and maintenance, that is, large components should not be placed around small components, and there should be enough space around components that need to be debugged. It will often become very embarrassing if it is too crowded.

How to arrange and connect PCB in a flexible and hard board factory

4. For the circuit parts of the same structure, use the "symmetrical" standard layout as much as possible; optimize the layout according to the standards of uniform distribution, balanced center of gravity, and beautiful layout. Baineng.com is a subsidiary of Qinji Group and is a leading domestic electronic industry service platform. It provides online components, sensor procurement, PCB customization, BOM distribution, material selection and other electronic industry supply chain complete solutions, one-stop to meet the electronics industry The overall needs of small and medium-sized customers in the industry.

5. The same type of plug-in components should be placed in one direction in the X or Y direction. The same type of polarized discrete components should also strive to be consistent in the X or Y direction to facilitate production and inspection.

6. The heating components should generally be evenly distributed to facilitate the heat dissipation of the veneer and the whole machine. Temperature sensitive components other than temperature detection components should be kept away from components that generate large amounts of heat.

7. High voltage and large current signals are completely separated from weak signals of small current and low voltage; analog signals are separated from digital signals; high-frequency signals are separated from low-frequency signals; the spacing of high-frequency components should be sufficient. In the layout of components, appropriate consideration should be given to placing the components of the same power supply as close together as possible to facilitate future power supply separation.

The above are the main considerations about "how to put" or layout. The "how to connect" is relatively more complicated, generally speaking:

Priority of key signal lines: Prioritize routing of key signals such as analog small signals, high-speed signals, clock signals, and synchronization signals;

Density priority principle: Start wiring from the most complicated devices on the single-board PCB. Start wiring from the most densely connected area on the board.