https://devzone.nordicsemi.com/f/nordic-q-a/94500/dc-blocking-cap-with-nrf52840-and-pifaHello, Do I have to include a DC blocking capacitor with nRF52840 if I use a PIFA antenna? Can you point me to some documentation (i.e., reference design) that would include capacitance value as well? Thank you.en-USTelligent Community 13Mon, 05 Dec 2022 19:36:17 GMThttps://devzone.nordicsemi.com/thread/399056?ContentTypeID=1Mon, 05 Dec 2022 19:36:17 GMT137ad170-7792-4731-bb38-c0d22fbe4515:fa62bea6-03f5-4847-b543-d5c278ad8b99Maxwell1864<p>Hi Priyanka,</p> <p></p> <p>Thank you for your answer. I am using a matching network. Nevertheless, I was more concerned about DC component being shorted to ground by the antenna configuration. I found out that&nbsp;output stage of the radio is transformer coupled so there is no DC component on the ANT ball. Hence I don&#39;t need a DC choke.</p> <p>Thank you.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/398984?ContentTypeID=1Mon, 05 Dec 2022 13:23:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ad066bac-9961-4e30-a0d6-77362fbf751aPriyanka<p>Hi Fabio,</p> <p>You can use any antenna matching network for this. But please keep in mind that the&nbsp;<span>nRF needs its own matching network as it is not 50 ohms from the ANT pin and it is also used for filtering the harmonics. Also, the antenna needs it&#39;s own matching circuit and for this,&nbsp;a single shunt capacitor can be used, with trace antennas&nbsp;in case you can adjust the length. You can refer any reference diagram for the same, from the hardware files on our website. It would be better to take a look at the <a href="https://www.nordicsemi.com/Products/Development-hardware/nrf52840-dongle">dongle hardware reference</a>.</span></p> <p><span>Best Regards,</span></p> <p><span>Priyanka</span></p><div style="clear:both;"></div>