PCB Antenna nrf52810 eagle files. Does it need extra components for impedance matching ??

[SwapnilMarathe]

Are the PCB antennas provided in eagle library of NRF52810 (github) require any additional components for impedance matching or i can directly add the PCB antenna to ANT in reference design provided at reference layouts

[Andreas]

Hi,

 

The quarter-wave monopoles only needs one parallel component  near the antenna feed, provided it is long enough.  This component comes in addition to the ones in the reference design, and can be seen as C15 in the nRF52-DK as an example. To make sure that the antenna is long enough it is recommended to make it a little longer than what is expected to be needed at first, then tune it and update your layout accordingly.

The meandering antennas (the ones that have multiple bends) quite frequently need an L network, and as you do not know which orientation the L-network will have before tuning it, space is typically reserved for a full pi network.

 

Best regards,

Andreas

[SwapnilMarathe]

Hi,

Quick question : 
I see that in NRF52-DK there is a item "J1 MM8130-2600" provided to connect external antenna
Can i just shunt that out of the circuit ??

Below, snap shot of antenna part of NRF52-DK hardware files (nrf52-dk hardware files)

[Andreas]

Hi,

 

If you do not plan to use it, simply remove it and make the trace from C13 go all the way to C15.

 

Best regards,

Andreas

[SwapnilMarathe]

Thanks !!