为避免地环路影响,几种好的接地方式

2019-07-14 12:53发布

Ø        (单点接地)The external shield, and the shields of all connectors, should be connected together. This external ground should be connected to the ground plane of the PCB at only one point; this avoids large current through the ground plane of the PCB. If the connectors are mounted on the PCB, the outer perimeter of the PCB should contain a strip of copper connecting to the shields of the connectors. There should be a break in copper between this strip, and the main ground plane of the circuit. The two should be connected at only one point. This way, if there is a large current between connector shields, it will not pass through the ground plane of the circuit. Ø        (星形连接)A star topology should be used for ground distribution, avoiding loops. Ø        (功率器件靠近电源)Power devices should be placed closest to the power supply, while low-power devices can be placed further from it. Ø        (差分信号传输)Signals, wherever possible, should be differential. Use differential signaling.