https://devzone.nordicsemi.com/f/nordic-q-a/9148/nrf51822-gpio-pins-have-clamping-diodeDoes nrf51822 gpio pin has clamping diode on it? if yes then how much current can the clamping diode sustain for long periods?en-USTelligent Community 13Fri, 11 Sep 2015 07:29:05 GMThttps://devzone.nordicsemi.com/thread/33705?ContentTypeID=1Fri, 11 Sep 2015 07:29:05 GMT137ad170-7792-4731-bb38-c0d22fbe4515:05ad5b7c-4a98-4774-b658-f01d7684b767MartinBL<p>This is not something we have tested so we will not provide any numbers.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/33704?ContentTypeID=1Thu, 10 Sep 2015 18:58:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3d095beb-43e9-46eb-a144-552c6e661c58Rushd<p>Thanks Martin. I understand that nrf51822 gpio pins clamping diodes arent designed as an alternative to a standard zener diode. But, Can I possibly get the estimated safe current and voltage rating for the clamping diodes? Of course I understand that this estimated information may cause the chip to be damaged and Nordic isnt supporting it to be used in this way.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/33703?ContentTypeID=1Thu, 10 Sep 2015 11:51:44 GMT137ad170-7792-4731-bb38-c0d22fbe4515:209dc8f4-a8fe-41db-8194-97d48c9099fcMartinBL<p>Hi</p> <p>Yes the GPIOs have clamping diodes. However, we usually don&#39;t want to go into discussions on how to operate our devices outside recommended operating conditions. I urge you to stay within maximum ratings e.g. by adding zener diodes, level shifters or resistor bridges to keep the voltages within limits.</p> <p>If you intend to use the GPIO pins as ADCs then you can find a relevant post on devzone here: <a href="https://devzone.nordicsemi.com/question/4241/what-is-the-maximum-current-through-clamping-diodes-in-nrf51822/">What is the maximum current through clamping diodes in nRF51822?</a></p><div style="clear:both;"></div>