chip antenna

[katrindqaws]

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?

[Bendik Heiskel]

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

[katrindqaws]

my board is 5mm*5mm, how i can find a tiny small antenna?

if i open antenna pin how it will be works?

[Bendik Heiskel]

Since your board is very small I recommend you contact some chip antenna manufacturers and have them recommend you a suitable antenna. Small PCBs are difficult for antenna performance, so getting help from the antenna manufacturers is highly recommended.

 

katrindqaws said:

if i open antenna pin how it will be works?

I'm not sure I understand what you are asking about. A antenna is required when using the radio. The image I shared only show where you need to add the antenna and antenna matching circuit recommended by the antenna manufacturer.

 

Best regards,

Bendik

 

[katrindqaws]

can i use external antenna?

how?

[Bendik Heiskel]

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:

[katrindqaws]

hi, would you introduce some small external antenna?