# Can the gpio pins of the electron be used as 3.3V supplies if set to HIGH?

**URL:** <https://community.particle.io/t/can-the-gpio-pins-of-the-electron-be-used-as-3-3v-supplies-if-set-to-high/53044>\
**Category:** Hardware\
**Tags:** electron\
**Created:** [November 1, 2019, 6:13pm UTC](https://community.particle.io/t/can-the-gpio-pins-of-the-electron-be-used-as-3-3v-supplies-if-set-to-high/53044 "2019-11-01T18:13:26Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![chri5](https://avatars.discourse-cdn.com/v4/letter/c/e56c9b/32.png) [@chri5](https://community.particle.io/u/chri5)\
**Post date:** [November 1, 2019, 6:13pm UTC](https://community.particle.io/t/can-the-gpio-pins-of-the-electron-be-used-as-3-3v-supplies-if-set-to-high/53044/1 "2019-11-01T18:13:26Z")

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Due to a design flaw, I may need to use a GPIO pin as the 3.3V supply for a sensor I am connecting to my Electron. Normally, I would obviously use the 3V3 pin for this but is there any downside to using any other GPIO pin set to HIGH as a voltage supply? The current draw should be well under 50mA (I cant find the max for the gpio pins in the documentation). Is there any downside to doing this?

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**Author:** ![picsil](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/picsil/32/21737_2.png) [@picsil](https://community.particle.io/u/picsil)\
**Post date:** [November 1, 2019, 6:52pm UTC](https://community.particle.io/t/can-the-gpio-pins-of-the-electron-be-used-as-3-3v-supplies-if-set-to-high/53044/2 "2019-11-01T18:52:28Z")

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Quick search of the forum turns up this:

> [@Electron I/O max current](https://community.particle.io/t/electron-i-o-max-current/25006):
>
> Hi! The Electron is documented so well, but I can’t figure out what the max current on the different GPIO pins is. (maybe just me. found 25 mA for the Photon on the forums) I need it to find a suitable transistor to switch 200 mA current on the 3.3V pin and if it is feasible to directly power 5 LEDs with 20 mA. Thanks in advance for points in the right direction. Cheers

Bottom line: stay under 25mA on the GPIO pins.

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**Author:** ![aklein24](https://sea2.discourse-cdn.com/flex026/user_avatar/community.particle.io/aklein24/32/23813_2.png) [@aklein24](https://community.particle.io/u/aklein24)\
**Post date:** [November 1, 2019, 9:27pm UTC](https://community.particle.io/t/can-the-gpio-pins-of-the-electron-be-used-as-3-3v-supplies-if-set-to-high/53044/3 "2019-11-01T21:27:54Z")

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what kind of sensor? The pins are PWM so the output will be noisy and could interfere with the readings. I tried using it with a thermistor (sub 1mA draw) so well below the 20 mA or so limit, and the particle device was fine with it, but my temperature readings were very inaccurate. Wound up just switching it off / on using a high-side transistor from the 3.3V pin.