hi all
i want to use a chip antenna for nrf52840
but un data sheet there is not any sample layout or component details
for example i want to use this chip antenna
https://alphamicro.net/wp-content/uploads/2024/11/AMC-ANT-2JL41-datasheet.pdf
how i can find proper chip antenna sample or component detail?
Hi,
Our reference schematics and layout include only the radio matching network and does not include any antenna specific matching circuit. Except for the development kit design files.
To use a chip antenna you simply add the matching components specified in the antenna datasheet after the nRF52840 radio matching network:
The same is done for the layout. But keep in mind that chip antennas often have a layout that must be followed precisely.
The antenna matching components are placed close to the antenna. Trace going between the end of the radio matching network and the antenna matching network must be a transmission line with an impedance of 50 Ohm. We recommend using a grounded coplanar waveguide. There are multiple tools available for calculating the correct dimensions required for a impedance of 50Ohm.
Once you have made a schematic and layout for your custom board you can create a private ticket where you share the design files with us for a review. This should be done before the boards are produced, so that any potential issues can be fixed.
Best regards,
Bendik
To use a external antenna you just need to add a connector after the radio matching network. External antennas are already matched to 50 Ohm, so no antenna matching circuit is needed. It's most common to use a U.FL connector for the antenna, but the connector type depends on the external antenna you choose to use.
Our DKs have a connector on them so you can copy parts of the DK design:
