Powering 5V Servo Motors - Do I need a zener diode?

Hi everyone, I am new here so I hope this post is under the correct tags.

I had a question related to the Powering the Pixhawk article. I need to use 2 micro servos for a drone. The power module I am using is the PMD03 power module which has 5V output pins, which I thought could be wired to the PWM rail of the Pixhawk (6x pro) to supply power to the servo motors.

However, the “Powering the Pixhawk” article discusses the use of a zener diode to protect the Pixhawk when you are supplying 5V to the PWM rail. I was not sure if I would need a zener diode in my case – from my understanding, the zener diode was only necessary if the PWM rail is being used as a backup power supply for the Pixhawk itself. I am not intending to use the 5V on the PWM rail as backup power, just to power the servos. Would I need a zener diode in this case?

Above is a wiring diagram. I am also not entirely sure where the 5V from the power module should be wired to the PWM rail on the Pixhawk, so it might be placed incorrectly in the diagram. Thank you for any help!

No diode required and you can wire it to any set of pins it’s a common rail.

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