Introduction to layout design of PCB circuit board

The density of PCB printed circuit boards is getting higher and higher, and the quality of PCB design has a great influence on the interference ability. Therefore, the layout of PCB is very important in design. Special component layout requirements:

1. The shorter the connection between high-frequency components, the better, try to reduce the electromagnetic interference between each other; the components that are susceptible to interference should not be too close; the input and output components should be as far away as possible;

2, Some components have a higher potential difference, should increase the distance between them, reduce common mode radiation. The arrangement of components with high voltage should pay special attention to the rationality of the layout;

3, the thermal element should be away from the heating element;

4, the solution capacitor should be close to the power supply pin of the chip;

5. For the layout of adjustable components such as potentiometers, adjustable inductors, variable capacitors, microswitches, etc., should be placed in a position that is easy to adjust as required;

6. The position occupied by the positioning holes of the printed board and the fixed bracket should be left.

General component layout requirements:

1. Place the devices of each functional circuit unit according to the flow of the circuit, so that the signal flow direction is as consistent as possible;

2. Centering on the core components of each functional circuit, the components should be arranged around the PCB, and the components should be evenly and neatly arranged on the PCB to minimize and shorten the leads and connections between the components;

3, the circuit working at high frequency, should consider the interference between components, the general circuit should be as parallel as possible to facilitate the wiring;

4, the layout of the PCB is not less than 80mil from the edge of the board. The optimal shape of the board is rectangular with an aspect ratio of 3:2 or 4:30.