we are using the nRF52840 and antenna signal i connected ceramic chip antenna(ACAG020-2450-T).
The above attached schematic of ant signal matching circuit schematic.
The below is the antenna datasheet link.
Kindly check the antenna area matching circuit.
Please suggest if any changes/modifications required ASAP.
C3, L2 and C8 belongs to the radio and takes care of impedance transformation and some harmonic attenuation.
So L1 and C3 remains as antenna tuning components. I recommend either adding a shunt component in parallel with C3 to make a PI-network for the antenna or a series component between L1 and the antenna for T-network. A PI-network is easier as it requires only one series component.
Thank you for the replay.
As per above i will add the component in parallel with C3. Should i add resistor or capacitor and what is the value for the same.
Kindly suggest the same.
Take a look at this white paper: https://infocenter.nordicsemi.com/pdf/nwp_017.pdf
Thank you for replay. I attached the schematic and layout.
The below is the Antenna link of ceramic antenna which is used in layout.
Kindly review the same.
Thanks and Regards
That won't work well. You need a ground plane on the top layer. Using tracks to connect ground is not going to work at these frequencies. Take a look at the reference layout to see how it's done.
C3, C8 and L7 shall be placed like this:
Note how C3 here is grounded only to the VDD_PA pin and the center pad.
It's _very_ important that you follow the antenna manufacturers reference layout:
(from the antenna datasheet)
Every dimension must be correct!