I'm a DAFE in Japan. Our customer is interested in ADM2867E due to Low Radiated Emissions. Then he wants to know the data of Radiated Emissions higher than 1GHz. Could you please give us it?
The data was gathered between 1GHz and 4GHz in anechoic chamber 3m from a horizontal antenna, which is the worst case orientation.
With peak detector the maximum emission from the evaluation board is 57dBuV/m @ 3.7GHz, 17dBuV/m margin to the EN55032 / CISPR Class B limit of 74dBuV/m.
With average detector the maximum emission is 51dBuV/m @ 3.7GHz, 3dBuV/m from the Class B limit of 54dBuV/m.
I am having difficulty sharing images on EZ at the moment, I will follow up with an image of the scan once the sharing issues are resolved.
Hi, Thomas from Austria- we have a issue with the radiation at 3.77 and 4.02 GHz, violating RX limits of EN 302 571. Until now we could not identfy if it is emitted directly from the chip or via the PCB. We used the reference design from the Datasheet.
the source is clearly the ADM2867E.
Do you have any hints how to improve this behaviour?
Could you share more details on the emission levels you are seeing with the device? I am surprised to see the 4.02GHz frequency appear from the ADM2867E.
If possible I would recommend reducing the size of the GND2 plane -> This will reduce the antenna area and form a less efficient dipole antenna. If this is not possible and you need a large secondary side ground plane, inductive/ferrite filter can be used to separate an small GND2 plane of the ADM2867E from the rest of the secondary side ground plane.