nRF52832 with Chip Antenna

RE: nRF52832 with Chip Antenna

Bendik Heiskel — Tue, 30 May 2023 06:37:06 GMT

[quote user="Nordix"]I assume that the matching circuit between ANT and the 50 Ohm trace should be located as close as possible to the ANT pin!?[/quote]

Yes, that's correct. One thing to note is that C3 must be grounded to the center GND pad with a trace through VSS pin 31. This is done to increase the filter performance at the 2nd harmonic frequency. Here is a snippet showing the correct ground configuration for this capacitor:

The full design and production files for the reference schematic can be downloaded here:

https://www.nordicsemi.com/Products/nRF52832/Download

Best regards,

Bendik

RE: nRF52832 with Chip Antenna

Nordix — Fri, 26 May 2023 15:36:27 GMT

Thank you very much for the quick reply. Quick follow-up: I assume that the matching circuit between ANT and the 50 Ohm trace should be located as close as possible to the ANT pin!?
Best,
Nordix

RE: nRF52832 with Chip Antenna

Bendik Heiskel — Wed, 24 May 2023 13:54:34 GMT

Hi,

Both networks are needed, the one in the nRF52832 reference circuit is matching the ANT pin to the 50 Ohm transmission line and is filtering out the harmonic frequency emission.

[quote user=""]Furthermore, is the length of the feed line important?[/quote]

The length feed line is not important, we recommend it is kept as short as possible. The only thing to keep in mind is to not make it 1/4 wavelength, roughly 30mm, as this may cause unwanted effects.

Best regards,

Bendik