Combining the RF circuitry of NRF52 DK and NRF51822 Dongle

[Gokul]

Please find attached the screenshot of the schematic where i have combined the RF circuitry from the NRF52 DK and the NRF51822 dongle for a compact board development. .

Is this schematic correct. Do i need to add the RF connector/switch provided in the NRF52 DK schematic. Kindly provide your suggestions / corrections.

[Hung Bui]

Hi Goku,

The schematic looks fine. You don't need the RF connector if you don't need one. However the value of R6, C3, L1 won't be the same as on nRF51 dongle. You would need to tune the value to have optimized rf performance. If you don't have equipment to tune the PI network, you can go for another option is to have only one shunt component (says C3) and then a longer antenna length. Then you can try to tune the antenna by reducing the length. It's described here at 4.1

The main point is to have 50Ohm antenna impedance before you connect to L1.