1. The PCB layout
design should fully comply with the design principle of placing along the signal flow direction in a straight line and avoid looping as far as possible.
2. Each filter capacitor should be placed as close as possible to the power supply pin of the chip
3. Whether the printed circuit board size is consistent with the mechanism size, and whether the component height meets the mechanism requirements
4. Crystal oscillator circuit should be close to IC to ensure the shortest crystal oscillator signal line
5. Avoid direct coupling of signals and affect signal quality
6. When multiple module circuits are placed on the same PCB
, digital circuit and analog circuit, high-speed circuit and low-speed circuit should be arranged separately.
7. Avoid mutual interference among digital circuit, analog circuit, high speed circuit and low speed circuit.
8. For high-quality components, the installation position and strength should be considered; the heating elements should be placed separately from the temperature sensitive elements; if necessary, the thermal convection measures should be taken;
9. Avoid high frequency circuit noise radiated out through the interface.
10. Energy storage and high frequency filter capacitors should be placed near unit circuits or devices with large current variation (such as input and output terminals of power modules, fans and relays).
11. The existence of energy storage capacitor can reduce the circuit area of high current circuit.
12. The filter circuit of power input port of circuit board should be placed close to the interface.
13. On PCB board, the filter, protection and isolation devices of interface circuit should be placed close to the interface, which can effectively achieve the effect of protection, filtering and isolation.
14. Strong radiation devices such as crystal, crystal oscillator, relay and switching power supply should be far away from the interface connector of single board.
15. The layout should be balanced, dense and orderly, not top heavy or heavy.
16. The closer the capacitance is to the pin, the smaller the area of the high frequency circuit, and the smaller the radiation.