Trouble with grounding higher current hobby servos

Community PCB Design
1

Hey guys,

I’m having a bit of trouble creating my project board. I’m using the atmega328p from the arduino on a custom pcb, and I’m not exactly sure how to wire up the servos. I’m using 2 HS-5645MG Hitec servos that apparently take between 2-2.5A at max torque.

Since the board will always be connected to 5V USB, but the battery won’t always be connected and the servos need to be grounded to the same ground as the micro to avoid interference, so I’m sort of skeptical of grounding to the USB port. From what I’ve seen from other schematics, people seem to wire the external battery (6V), the servos, and the micro all to common ground through the usb port. Is this ok?

Any help would be appreciated!

2

I’m not sure I understand your concern. In order for the ATMega to control the servos they will have to share a common ground. In order for USB to connect to the ATMega, they will have to share a common ground. Hooking all 3 to a common ground won’t hurt anything.