https://devzone.nordicsemi.com/f/nordic-q-a/20332/pca10040-power-measurementI&#39;ve modded the PCA10040 DK for current measurement with an ampere-meter (TTi 1604), using a program which turns an LED on and off every 5 seconds. The measured current stays at around 3uA regardless of whether the LED is on or off. However, the poweren-USTelligent Community 13Fri, 10 Mar 2017 10:00:45 GMThttps://devzone.nordicsemi.com/thread/79223?ContentTypeID=1Fri, 10 Mar 2017 10:00:45 GMT137ad170-7792-4731-bb38-c0d22fbe4515:95deb8fb-8a7e-4e62-a708-41b16cd71750Steve H<p>Great, thanks for the clarification Stian.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/79222?ContentTypeID=1Fri, 10 Mar 2017 09:47:29 GMT137ad170-7792-4731-bb38-c0d22fbe4515:7b98b1f3-7aa3-4ce2-a68b-3ede240cd75bStian R&#248;ed Hafskjold<p>Hi,</p> <p>The LEDs are powered by VDD, which is from the external power pins, Battery or USB. The nRF chip is powered by VDD_nRF. The link between VDD and VDD_nRF is P22 where you are measuring current, so the only thing you are measuring on P22 is the current going in to the nRF.</p> <p>When you are turning on the LEDs from the nRF chip, you are pulling the GPIO to ground. Which means that current is flowing directly from VDD (power supply) through the LED, down to GND. Not going through the chip, or P22.</p><div style="clear:both;"></div>