I have an adafruit 16 port servo driver. In the directions on their webpage, they explain how to wire it, as well as connect an external power supply. They mention not to plug the power directly into the raspberry pi, as it can cause a brownout.
Don't try to power your servos from the RasPi's 5V power, you can easily cause a power supply brown-out and mess up your Pi! Use a separate 5v 2A or 4A adapter
The RaspberryPi has a 5v GPIO pin, and I was wondering what the chances of causing a brownout were, and how this could be prevented.
It would be easier for me to wire it directly to the Pi, however, I would like not to break it.