I have currently EMI-issues within AM and DAB frequencies. In AM I see 3rd and 5th harmonic. Therefore, I'm sure this comes from the data transition (115200 baud). In DAB band (175 – 239 MHz) I see also violations cause by the system. This is in the range of the 3000th to 4000th harmonic. Unfortunately, I'm not the owner of the design and I'm not able to get more details from the measurement, at the moment. I believe harmonics in this range are unusually. Therefore, I'm looking for other reasons and I come to the point to find out what is the switching frequency of the included charge pump?
Regards, Guido
