A circuit board is a support element for a circuit element and device in an electronic product. Even if the circuit diagram is properly designed and printed circuit board is not properly designed, it will also have an adverse impact on the reliability of electronic products. In the design of printed circuit boards, attention should be paid to the correct method, to comply with the general principles of PCB design, and should meet the requirements of anti-interference design.

To make the best performance of electronic circuits, the layout of components and wiring is very important. In order to design PCB with good quality and low cost, the following general principles should be followed:

The following principles shall be observed when determining the location of a particular component:

1* as far as possible to shorten the connection between high frequency components, and try to reduce their distribution parameters and electromagnetic interference. Vulnerable components should not be too close to each other, and input and output components should be kept as far away as possible.

2* some components or wires may have higher potential difference, should increase the distance between them, so as not to discharge lead to unexpected short circuit. The components with high voltage shall be arranged as far as possible when the hand is not touched at the time of debugging.

3* components weighing more than 15g shall be fixed with brackets and welded. Those large, heavy, and more heat components should not be installed on the printed board, but should be installed in the chassis of the whole machine chassis, and should consider the problem of heat dissipation. The heat sensitive element shall be away from the heating element.

4* for potentiometer, adjustable inductance coil, variable capacitor, micro switch and other adjustable components layout, should consider the overall structure of the machine. If the machine is adjusted, should be placed on the printed board to facilitate the adjustment of the place; if outside the adjustment, and its position to adjust the knob in the box panel on the position of adaptation.