https://devzone.nordicsemi.com/f/nordic-q-a/48145/high-current-consumption-1-ma-on-uart-tx-pin-4-but-not-on-all-pinsI use nRF52832 and SDK 15. Using the PPK, I measure a floor of about 1 mA that stay in SYSTEM_OFF mode. Debugging in more detail, I found that it&#39;s due to the UART setup and more precisely when the TX pin is connected to P.04 ! But this pin is not connecteden-USTelligent Community 13Thu, 06 Jun 2019 07:19:15 GMThttps://devzone.nordicsemi.com/thread/191238?ContentTypeID=1Thu, 06 Jun 2019 07:19:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e2afad24-d2db-4c92-bef0-8890023d876dThierryC<p>Yes, apparently we have some lower resistance on TX in some devices we are using (our prototype, not a DK). We have to understand how it happens.<br />Anyhow thanks for the hint !</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/191093?ContentTypeID=1Wed, 05 Jun 2019 12:11:29 GMT137ad170-7792-4731-bb38-c0d22fbe4515:83b7e65a-40d1-4cc5-8d87-d2edca55d123Kenneth<p>I agree with you, based on the nRF52-DK there is nothing hooked to P0.04. Have you tried to measure with a multimeter if there is any resistance on the pin, and/or if you by software may have added some kind of pull-down on the pin?</p> <p>What is the revision of the nRF52-DK you are using?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/190803?ContentTypeID=1Tue, 04 Jun 2019 13:45:27 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9b5d5822-854a-4cee-bd24-e3f358d41429ThierryC<p>Looking more on the issue, it seems not necessary related to UART. If I set this TX pin (P.04 in my case) to &quot;Output High&quot;, I got this power consumption, but not if I set it to Input or &quot;output Low&quot;. But on the HW, there&#39;s (should be) nothing connected to this pin, just a connector.</p><div style="clear:both;"></div>