The density of PCB printed circuit boards is getting higher and higher, and the quality of PCB design has a great influence on the ability of anti-interference, so the layout of PCB is in a very important position in the design. Layout requirements for special components:

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

2. Some components have a higher potential difference, so the distance between them should be increased to reduce common mode radiation. Pay special attention to the rationality of the layout of components with high voltage;

3. Thermal components should be far away from heating components;

4. The solution capacitor should be close to the power pin of the chip;

5. The layout of adjustable components such as potentiometers, adjustable inductance coils, variable capacitors, micro switches, etc. should be placed in an easy-to-adjust position as required;

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

Layout requirements for common components:

1. Place the components of each functional circuit unit according to the circuit process to make the signal flow direction as consistent as possible;

2. Take the core components of each functional circuit as the center and lay out around it. The components should be evenly and neatly arranged on the PCB to minimize and shorten the leads and connections between the components;

3. For circuits operating at high frequencies, the interference between components should be considered. In general, the components should be arranged in parallel as far as possible to facilitate wiring;

4. The outplace line of the PCB is generally not less than 80 mils from the edge of the circuit board. The best shape of the circuit board is rectangular, and the aspect ratio is 3:2 or 4:30.