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I have a setup where I need to control a solenoid-valve via a microcontroller. The solenoid-valve needs a 50ms \$\pm\$6V with around 250mA to OPEN and another 50ms pulse of now inverted \$\mp\$6V to CLOSE again.

My idea was to use a MOSFET 2N/2P-CH array (TC8220K6-G). Attached the idea of my circuit.

Now I know, that solenoid do kick-back voltage due to their inductance and one should use a flyback diode. The problem is, that in my case I would need to put 2 Diodes in each direction which would result in a short circuit.

Any idea how to deal with this problem? Or has someone a better idea to control such pulse valve?

Schematics

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I think I found the solution in using a TVS-Diode. Its basically two back-facing Zener diodes that will only let current flow if a certain threshold voltage is reached. Since I need 6V for the solenoids, I can take a TVS-Diode rated at 7V so only the kick-back voltage will be absorbed.

Also in another thread, I found that using a H-Bridge motor controller (BD6221F-E2) might be a better choice then the MOSFET Array. You can invert the voltage output by using the forward vs. reverse pin of the motor controller.

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There is no need to do anything regarding the reverse voltage surge. Since when the solenoid is non active, both p-channel mosfets are conducting. So, it is as if there is low resistance connected in parallel to the solenoid. So, the voltage surge is drained through that low resistance.

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