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

1. The shorter the connection between the high-frequency components, the better, to minimize the mutual electromagnetic interference; 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 high potential difference, the distance between them should be increased to reduce common mode radiation. The layout of components with high voltage should pay special attention to the rationality of the layout;
3. Thermal components should be kept 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, and micro switches should be placed in positions that are convenient for adjustment as required;
6. The position occupied by the positioning hole of the printed board and the fixing bracket should be reserved.
Layout requirements for common components:
1. Place the devices of each functional circuit unit according to the circuit flow, so that the signal flow direction is as consistent as possible;
2. Take the core components of each functional circuit as the center and make layout around it. The components should be evenly and neatly arranged on the PCB, and the leads and connections between the components should be minimized and shortened;
3. For circuits working at high frequencies, the interference between components should be considered. In general circuits, the components should be arranged in parallel as much as possible to facilitate wiring;
4. The outplace line of the PCB is generally not less than 80mil from the edge of the circuit board. The best shape for the board is a rectangle with an aspect ratio of 3:2 or 4:30.