nRF52811 Antenna Design

RE: nRF52811 Antenna Design

mathiaso — Mon, 21 Oct 2024 12:43:36 GMT

Could you please elaborate? You'll need the 32 MHz crystal to, e.g., operate the radio, as explained in the clock control section of the PS.

RE: nRF52811 Antenna Design

Kaveh.M — Thu, 17 Oct 2024 16:58:27 GMT

Thanks. For clock, the 32.768kHz option is sufficient or I have to use 32MHz crystal as external clock source?

RE: nRF52811 Antenna Design

mathiaso — Thu, 10 Oct 2024 12:38:22 GMT

Yes, that would be sufficient. The bare minimum would actually be VDD, GND, SWDIO, and SWDCLK.

Through SWDCLK and SWDIO you can interface directly with a debugger, as shown in the debug section of the PS.

RE: nRF52811 Antenna Design

Kaveh.M — Wed, 09 Oct 2024 14:22:38 GMT

Thanks. For programming this chip, I see on the pins there are only VDD, GND, RESET, SWDIO, SWDCLK are available. Are these pins sufficient (SWO seems missing) and can they be directly interface with a Segger J-Link Debugger for programming the chip?

RE: nRF52811 Antenna Design

mathiaso — Tue, 08 Oct 2024 09:00:57 GMT

If you have a look at the GPIO pins mentioned under GPIO pins located near the radio, you'll see that those GPIOs aren't present in the WLCSP ball assignments. That's why there is no mention of the WLCSP package.

RE: nRF52811 Antenna Design

Kaveh.M — Mon, 07 Oct 2024 18:12:03 GMT

Thanks. Also in the datasheet for nRF52811, there is recommendations for using GPIOs close to RF antenna port in section "7.1.4 GPIO pins located near the radio". In this section there are recommendations only for QFN package and nothing mentioned for CAAA WLCSP package.

Are there recommendations for using GPIOs near RF antenna port of nRF52811 CAAA WLCSP package?

RE: nRF52811 Antenna Design

mathiaso — Mon, 07 Oct 2024 14:37:13 GMT

Yes, please have a look at the nRF52811-CAAA's reference layout which can be downloaded from here.

RE: nRF52811 Antenna Design

Kaveh.M — Mon, 07 Oct 2024 13:47:08 GMT

Thanks. Is there a PCB layout example or recommendation of footprint for nRF52811 CAAA WLCSP package.

I can see in the datasheet there is just an example for QFN48 package.

RE: nRF52811 Antenna Design

mathiaso — Thu, 03 Oct 2024 08:29:08 GMT

Hi, Kaveh.

We have this white paper describing how to design a λ/4 PCB monopole antenna for 2.45 GHz. Beware that there are other factors as well, in addition to the antenna, that impact the wireless performance.

Best regards,
Mathias