What are the principles of PCB board design and layout

In the PCB board design, the unit of the circuit board should be analyzed, and the layout design should be carried out according to the function. So, what are the principles of PCB board design and layout?

1. Under normal circumstances, all components should be placed on the same side of the circuit board. When the top components are too dense, some devices with limited height and low heat can be placed. The chip IC is placed on the lower layer.

2. Under the premise of ensuring electrical performance, components should be placed on the grid and arranged in parallel or perpendicular to each other to keep it clean and beautiful. Under normal circumstances, the components are not allowed to overlap; the components are arranged compactly and evenly distributed.

3. The minimum distance between adjacent components should be less than 1MM.

4. The edge of the board is not less than 2MM. The best shape of the board is rectangular, with an aspect ratio of 3:2 or 4:3.

5. Arrange the position of each functional circuit unit according to the circuit flow, so that the layout is convenient for signal circulation and the signal is as consistent as possible.

6. Center and surround the core component of each functional unit. The components are uniformly and compactly arranged on the PCB to minimize the shortening of the leads and connections between the components.

7. When making the package library, pay attention to the one-to-one correspondence between the schematic pins.

8. The layout of the IC decoupling capacitors should be as close as possible to the IC power supply pins, and the loop formed between the power supply and the ground should be as short as possible.

9. When placing components, consider that devices using the same power supply should be placed together as much as possible to facilitate future power supply separation.

10. After the layout is completed, print out the assembly drawing for the designer to check the correctness of the device package and confirm the signal correspondence between the SMT PCB board, backplane and connector. After confirmation, you can start wiring.