For our solenoid driver, we have individual transistors for driving each output, which means that we need to protect them with flyback diodes.

The important things we need for a flyback diode are to handle the maximum reverse voltage (30V or so) and be fast—there is a peak current of an amp or so, but it's near-instantaneous, so we're not as worried about continuous current.

We'll also need 8, so let's make sure they're not too expensive!

See the chosen part on DigiKey https://www.digikey.com/short/prdhzvw1

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