As shown below, I used the LF253 and the OPA2354AIDDA to build a voltage sample circuit, which is used on a grid-connected inverter for the line-to-line voltage. Unfortunately, the result is unsatisfactory.The BDin0 port is connected to my DSP, and the AD's output is shown as following picture. It seems that the three line-to-line voltage is well, but the Ud Uq after the pll is bad.
From the oscilloscope waveforms (as showm below), the power supply of LF353 has a serious common-mode noise, and the output has the same noise. I want to know if the noise will input the DSP and disturb the AD sample result, and if I need change the LF353 to another amp.