Is this ok to power the servos from USB?

Is it ok to link a wire from “5V Out” to the batt+ in order to power the servos from the USB?
Was the power-vin linkage supposed to do the same thing? Because that method doesn’t work.


No, it is not OK, and we have a FAQ about that. Also, Vin, USB power, and the +5V(out) pin are all different. See the Micro Maestro Pinout and Components page of the User’s Guide for more information about the different power levels on the board.

Specifically: Vin is an input to the board’s 5V regulator, typically connected to a battery or wall-powered power source. The +5V(out) is an output from that regulator, which gives you access to about 20mA of regulated 5V power. The USB power line can supply 100-500mA (not enough for a servo), and it is not made available on the board.


Would this be ok if the only “servo” is an ESC which doesn’t need barely any amp draw compared to a servo.

On thinking about this. Normally the ESC powers the Receiver at 5v from their that powers receivers. So I’d imagine the ESC will power the rail itself anyway. SO it will look after itself and a servo or two if I wish. Does that sound right to you guys.

Hello, Volition.

It is not entirely clear what it is you are asking, but it sounds like you are asking if the 5V BEC on your ESC can be connected to the PWR rail on the Maestro board. If that is the case, you would have to check if your particular ESC can provide enough current for the one or two servos you want to control.

If you are asking about something else, can you send a schematic that shows your proposed connections?


Thanks for your reply Jon

So the 5v BEC power will come from from my ESC it is that i am wishing to control. I won’t be adding any servos. Not in my initial design anyway.
The polulo micro maestro replaces my receiver in a RC car. I’m building a RC Dyno and this will allow me to program repeatable throttle inputs.

From my thinking putting a battery pack or a power supply might cause problems. As the ESC is both a power source and a servo output.

Does that make more sense?

Think this answers it.

Old post

I wonder though, normally my ESC in the car Powers a steering servo through the receiver. I’d assume it can power at least 1 servo.

Like I mentioned in my initial response to you in this thread, you would have to check if your particular ESC can provide enough current for the 1 servo you want to control. In general, I recommend that the BEC on your ESC provide enough current to handle the stall current of your servo. If you do not know the stall current of your servo, you might try looking inside its datasheet or product page.


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