GROUNDING
The use of ground and power planes is encouraged as a method of proving low impedance returns for power supply and signal currents. Ground and power planes can also help to reduce stray trace inductance and to provide a low thermal path for the amplifier. Ground and power planes should not be used under any of the pins of the AD8000. The mounting pads and the ground or power planes can form a parasitic capacitance at the amplifiers input. Stray capacitance on the inverting input and the feedback resistor form a pole, which degrades the phase margin, leading to instability. Excessive stray capacitance on the output also forms a pole, which degrades phase margin.
在运放AD8000中看到这么一段话，平时听到都是保持完整的平面，这里说在焊盘下面不要使用地平面和电源平面，觉得困惑，是否需要这么做呢？还有这里的指的是要删除整个芯片下面的平面，还是仅仅对每个焊盘下的对应小区域进行挖空处理？ |
楼主
标题置顶
标题高亮
