# Teensy 4.1 to control solenoid coil

**URL:** <https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137>\
**Category:** Development Boards, Kits, Programmers\
**Tags:** adafruit-industries-llc, sparkfun-electronics, evaluation-boards, tech-tips\
**Created:** [February 16, 2022, 3:07am UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137 "2022-02-16T03:07:04Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![WHFarms](https://avatars.discourse-cdn.com/v4/letter/w/ecae2f/32.png) [@WHFarms](https://forum.digikey.com/u/WHFarms)\
**Post date:** [February 16, 2022, 3:07am UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137/1 "2022-02-16T03:07:04Z")

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I have a solenoid coil that operates with the attached specs

 ![image](https://global.discourse-cdn.com/digikey/original/3X/7/f/7feef1ec9248b524106eaaed9d78deb77c093360.jpeg)

I want to drive it using teensy 4.1 but am looking for help getting the correct components between the teensy and the coil. I expect to integrate this into a pcb in the near future.

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**Author:** ![David\_1768](https://sea2.discourse-cdn.com/digikey/user_avatar/forum.digikey.com/david_1768/32/9762_2.png) [@David\_1768](https://forum.digikey.com/u/David_1768)\
**Post date:** [February 16, 2022, 2:59pm UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137/2 "2022-02-16T14:59:27Z")

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Welcome to the DigiKey TechForum WHFarms.  
I’m not familiar with the teensy 4.1, but you will need some type of relay that can be controlled by the teensy 4.1, and the contacts for the 12VDC @ 1A to activate the solenoid. The main question would be what voltage and current can you output from the teensy 4.1 to activate the relay?

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**Author:** ![rick\_1976](https://sea2.discourse-cdn.com/digikey/user_avatar/forum.digikey.com/rick_1976/32/1571_2.png) [@rick\_1976](https://forum.digikey.com/u/rick_1976)\
**Post date:** [February 16, 2022, 4:45pm UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137/3 "2022-02-16T16:45:47Z")

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Teensy I/O outputs are 3.3V if I understand correctly, so a low-threshold FET would be needed. One of [these](https://www.digikey.com/short/tj1z7bhz) would likely work.

Some means of dissipating energy in the coil inductance during turn-off is also needed. A [diode](https://www.digikey.com/short/qp98dzhp) across the controlled relay is the simplest and least component-specific solution, but there are other solutions offering different advantages and disadvantages.

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**Author:** ![WHFarms](https://avatars.discourse-cdn.com/v4/letter/w/ecae2f/32.png) [@WHFarms](https://forum.digikey.com/u/WHFarms)\
**Post date:** [February 16, 2022, 5:35pm UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137/4 "2022-02-16T17:35:01Z")

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The teensy does indeed run at 3volts. The coil today connected to the manual potentiometer on the tractor reads 11 volts and about .5 amps.

I’m thinking I need some type of driver connected to the teensy that can be used to turn on and off battery voltage to the coil.

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<div class="post-metadata">

**Author:** ![rick\_1976](https://sea2.discourse-cdn.com/digikey/user_avatar/forum.digikey.com/rick_1976/32/1571_2.png) [@rick\_1976](https://forum.digikey.com/u/rick_1976)\
**Post date:** [February 16, 2022, 11:18pm UTC](https://forum.digikey.com/t/teensy-4-1-to-control-solenoid-coil/20137/5 "2022-02-16T23:18:14Z")

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> [@WHFarms](#):
>
> I’m thinking I need some type of driver connected to the teensy that can be used to turn on and off battery voltage to the coil.

That’s correct. The diode and transistor suggested could be connected to the coil as such to do the job.  
 ![image](https://global.discourse-cdn.com/digikey/original/3X/2/2/22580040c5078de1a45917b2a7275f563160c084.png)