VOH/VOL worst case

VOH/VOL worst casehttps://devzone.nordicsemi.com/f/nordic-q-a/48727/voh-vol-worst-caseA couple questions about the nRF52840 GPIO Electrical Specification: 1. In the nRF52840 GPIO Electrical specification, VOH at 0.5mA is spec'd to go as low as VDD - 0.4V, and up to VSS + 0.4V. If the device is connected to another digital input, theen-USTelligent Community 13Thu, 20 Jun 2019 13:20:24 GMTRE: VOH/VOL worst casehttps://devzone.nordicsemi.com/thread/193897?ContentTypeID=1Thu, 20 Jun 2019 13:20:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b9d6c214-e492-4542-a574-fc147d2d8c6aJeff<p>Thanks!</p><div style="clear:both;"></div>RE: VOH/VOL worst casehttps://devzone.nordicsemi.com/thread/193714?ContentTypeID=1Wed, 19 Jun 2019 14:18:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e81b04fb-23b6-4a10-8e10-e26e0f159c8ahaakonsh<ol> <li><span>The </span><span>VDD - 0.4V and VSS + 0.4V specs are extremely conservative.<br />The 52840 is similar to the 52832's gpio spec:  <a title=" GPIO Electrical Specification " href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/gpio.html?cp=3_1_0_19_3_0#unique_1511470077">GPIO Electrical Specification</a>:<br /><br />From Figure 3, you'll see that a source current of 0.5mA will yield a voltage drop of ~0.1V, which is far less than the spec's 0.4V.<br />A source current of <10µA will yield a much lower voltage drop than that again, you can also reduce the voltage drop further by using high drive strength instead of normal. See Figure 4.<br /><br /> Figure 3 and 4 are simulated worst-case scenarios btw, the reality will be somewhat different. <br /><br /></span></li> <li><span>From <a title="Absolute maximum ratings" href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/abs_max_ratings.html?cp=3_1_0_4#abs_max_ratings">Absolute maximum ratings</a>: VDD + 0.3 V or 3.9V if VDD > 3.6V. </span></li> </ol> <p> </p><div style="clear:both;"></div>