I am designing pcb for AT86RF215M tranceiver. The datasheet for it states that:
AVSS is the analog ground; DVSS is the digital ground voltage. The analog and the digital grounds should be separated on the PCB and only connected at a single point on the PCB.
So I guess that digital and analog ground should be connected at one point near the power supply. The problem is that evaluation board ATREB215-XPRO does not follow that rule. It is 4 layer PCB.
Signal GROUND POWER GROUND
The analog and digital pins are connected to via. Ad via is connected to both ground layers. Both two GROUNDS.
I don't know what approach is better? I can't figure out.