nRF52 PCB design - chip antenna required?

RE: nRF52 PCB design - chip antenna required?

Ronnie Tango — Mon, 23 Nov 2015 08:10:15 GMT

Great thanks!

RE: nRF52 PCB design - chip antenna required?

Einar Thorsrud — Mon, 23 Nov 2015 07:46:48 GMT

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

RE: nRF52 PCB design - chip antenna required?

Ronnie Tango — Fri, 20 Nov 2015 14:14:35 GMT

Thanks - but more what I meant was where should the Pi-network+chip antenna combination be placed, relative to the RF choke and "RF" pad in the reference design? Is the "RF" pad important?

RE: nRF52 PCB design - chip antenna required?

Einar Thorsrud — Fri, 20 Nov 2015 13:05:39 GMT

Yes, the Pi network is required when using a chip antenna. It should be as close to the chip antenna as possible.

RE: nRF52 PCB design - chip antenna required?

Ronnie Tango — Fri, 20 Nov 2015 11:48:27 GMT

Great, thanks. Also, to check I've understood the info in other posts - if using a chip antenna, it is necessary to include a matching (Pi) network in addition to the RF choke network (L1 and C3), in order to match the antenna to 50 Ohms?

Is the physical placement of the Pi-network important? Should it be immediately after L1, or after the rectangular pad marked "RF" in the reference design?

RE: nRF52 PCB design - chip antenna required?

Einar Thorsrud — Thu, 19 Nov 2015 13:35:58 GMT

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.