I am frantically trying to get my pixhawk running on my heli after my clone PX4 died. I currently have a BEC on order, but until then I am trying to work out a quick and dirty way to power my board.
Question is, what is the risk associated with powering pixhawk off the servo rail with a zener to limit peaks? I read that it is generally not recommended, but seriously how bad is the risk that the zener wont stop peaks?
Hmmm… sorry, I don’t have a good answer, especially because every setup is different. You do know that if you are trying to power the Pixhawk from the servo rail, you’ll have to use only 5V on the servo rail correct? It won’t accept more than 5.7V, and you need a little wiggle room.
You should use some capacitance on the servo rail to help. 4700uF at least.
I actually tried to power mine like this, but in bench testing, I got some brownouts so, best be careful.