nRF52 PCB design - chip antenna required?

[Ronnie Tango]

Hi,

Apologies if this is an obvious question, but I haven't been able to establish from previous questions or the data sheet whether it is necessary to use an external chip antenna when designing boards with the nRF52? Or is the small rectangular pad in the reference design marked "RF" (toward the bottom right corner) a PCB antenna in itself?

Thanks!

[Einar Thorsrud]

You can use a PCB antenna. The nRF52-DK has a PCB antenna on the top layer, this is on the part of the board that sticks out a bit on the right side, with the Nordic logo printed on it. You can see this in the reference layout.

[Einar Thorsrud]

The point marked "RF" is the 50 ohm reference plane, and the pi network and chip antenna comes after that.