TMS320F28335: 关于电机相电流采集的疑问

我直接复制工程师的原文了，这样方便理解一些：

It is true that the noise is heavy. Precision in current acquisition is a long signal chain issue. Starting from sense resistor, or any inline sensor, followed by analog circuits and components, to timing of sampling instance and length of sampling (window). In general, current sensing should be precise for better torque control. So it is always a good idea to improvise on the sensing hardware. However, that alone does not make it better. You have to ensure to sample the sensed signal when the inverter is not switching so that there is no switching noise or ground jitters at the time of sampling. Besides, you have to ensure there is sufficient sampling window for the internal hold cap to capture the signal being sampled. This will require the sensing circuit to provide low source resistance to the S/H cap to charge it faster. Hope it helps.