Other Parts Discussed in Thread: ISO7741
During module-level EMC test, we found one board assembly with iso7721 failed at two frequency points.
To exclude the effect on the whole test, we tested the power module(AC-DC module) first, and it passed.
But when the suspect board is powered, and no input/output was connected to the board. Its EMI energy exceeded limit(EN55032 Class A) more than 10 dB in 414MHz and 830MHz.
I checked the iso7721 datasheet, Iguess the modulation scheme may cause the EMI over range.
please help investigate this issue.