What is the tether voltage used for?


Hi everybody,

I noticed that the voltage on the tether is 5 volts and there is also 12.64 volts on the batteries. I am assuming the 12.64 volts are used to power up the control board and the ESCs, but I'm unaware what the tether's voltage is being used for. Any help would be appreciated.


Hi Patrick:

The 5V signal on the tether is used to signal the ROV to turn on.



Hi Walt:

Thank you for your reply. I'm trying to draw an easy to understand diagram for the OpenROV with its respective components and their voltages. This is for research purposes, and we are trying to figure out ways to make the system autonomous. We have an OpenROV at the lab but its currently being used and I can't get my hands on it yet. I have looked at the schematics provided and watched some of your videos. So far I know, and please correct me if I'm wrong, that the batteries provide the control board around 12.64 volts, which then gives 5 volts to the BBB, 5 volts to each ESC (and 10A according to schematic?), and 3.3V to the communication board. The tether gives 5V. What I can't find is:

1) How much voltage is required to power up the top side adapter? I believe the communication board requires 3.3V, but there is also the OpenROV Top Side Interface board which I am assuming requires 5V from the computer and then powers up the communication board and is also the source of the 5V signal on the tether as well?

2) Is the voltage required for the servos between 4.8V and 6V? (I got this from the store information on the recommended source)

3) Not too important but would still be nice to know how much voltage is required for the USB Camera? I'm assuming around 5 volts?

Thank you in advance.


1. The Homeplug adapter needs 3.3 Volt. Theres is small circuit Bord in the Top Side Interface witch transfers the USB 5 Volts to 3.3 Volts. 5 Volt USB from the Computer (USB-Connection). In my 2.4 Version, I am not sure if it is still used.

3. The Cam is USB Powered so yes: 5 Volts.


I am curious where did you find the schematics for the voltages?