PCB Antenna connection of nRF52810

RE: PCB Antenna connection of nRF52810

nunjjaram — Mon, 08 Jun 2020 10:15:11 GMT

Andreas, Thank you very much

RE: PCB Antenna connection of nRF52810

Andreas — Thu, 04 Jun 2020 07:12:16 GMT

Hi,

1. It might not be that simple, the track as described in the attachment leads into the radio (pin 20, GND), whereas in your design there is still some distance between what you define as 'ground' and the same point inside the radio. Impossible to say what effect this will have.

2. I strongly recommend you do so, this has been verified for 5+ years and there is nothing keeping you from replicating this. Your other alternative will probably work, but you will likely get a harder time tuning the filter, worst-case having to sacrifice some performance for compliant harmonic emissions, but why risk it.

Best regards,

Andreas

RE: PCB Antenna connection of nRF52810

nunjjaram — Wed, 03 Jun 2020 15:57:44 GMT

Hi, Andreas.

Thank you very much for your answer.

I have questions.

1. According to the contents of your attachment, can you see the same effect if we connect the GND and C22(our pcb design) with the length (about 0.9mm) and width(about 0.25mm) shown in the nordic reference design?

2. If not, I have to follow the reference design due to the special features of Pin 20/VSS? \

Thank you and Best Regards,

Sungsuk Han.

RE: PCB Antenna connection of nRF52810

Andreas — Tue, 02 Jun 2020 13:00:26 GMT

Hi,

See the explanation here: devzone.nordicsemi.com/.../nRF52-matching-network.pdf

Without this harmonic filtering will be degraded, and you might fail regulatory requirements for unwanted emissions. You might be able to tune the filter by adjusting C3 and L1 slightly, but you risk having to lower the output power to pass the requirements. You might still have to tune C3 and L1 slightly, but this will be much easier and generally result in better performance in the end. We therefore recommend that you ground C3 this way if possible, in your current layout I do not see any reason not to do this.

Best regards,
Andreas