1. Custom PCB fabrication follows the layout principle of “first big, then small, first difficult and easy”, that is, important unit circuits and core components should be prioritized.
2. The layout should refer to the principle block diagram, and arrange the main components according to the main signal flow direction of the board.
3. The arrangement of components should be easy to debug and repair, that is, there should be no space around the small components, and there should be enough space around the components to be debugged.
4. For the same structural circuit part, use the "symmetric" standard layout as much as possible.
5. Optimize the layout according to the standard of uniform distribution, balance of center of gravity, and beautiful layout.
6. The same type of instrumented components should be placed in one direction in the X or Y direction. The same type of polar discrete components must also strive to be consistent in the X or Y direction for ease of production and inspection.
7. The heating elements should be evenly distributed to facilitate the heat dissipation of the single board and the whole machine. Temperature sensitive components other than the temperature detecting components should be kept away from the components with large heat generation.
8. Custom PCB fabrication layout should try to meet the following requirements: the total connection is as short as possible, and the key signal line is the shortest. High voltage, high current signal and small current, low voltage weak signal are completely separated. Analog signal is separated from digital signal. The frequency signal is separated from the low frequency signal. The interval between the high frequency components should be sufficient.
9. 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 the power supply and the ground should be the shortest.
10. When customizing the layout of PCB components, it should be considered that devices using the same power supply should be placed together as much as possible to facilitate future power separation.