Arduino Servo power

I'm running 3 servos with a motor shield and I was wondering if I really need the shield?

Can I run 3 servos straight off the Arduino if I supply the +5v separately? Can the board handle that?

You can connect the servo signal line to the Arduino digital output pins - that's the normal thing. The servos should have their own power supply with a common connection to the Arduino ground - I presume that's what you have in mind.


Yes, thanks, but 3 servos, connected to pins 9, 10, & 11, with their own +5~6v supply would work? without the need for a motor shield?

I guess the motor shield is more for multiple DC motors, since the Arduino board can only handle 2 small motors at best.

An Uno can control a lot more that 3 servos.


The photo I added shows my breadboard with servo wire extensions on the bottom. The yellow wires are the signals going to the UNO. The other two (GND and +) connected to an external power source. My servos have a max voltage of 7v. My robotic arm has three servos, sharing the same power source, the strength of the power source will diminish the more servos connected. They take so many amps. In the picture on top of the uno is a sainsmart motor shield that I use for a stepper motor. It can motorize 2 servos, but because the stepper requires more voltage, as my shield is prepped for ext power for the stepper, I cannot use it for servos. Hope that helps.

Thanks. I did remove the motor shield and ran 3 servos off just the Arduino Uno; pins 9, 10, & 11, with a separate +5v supply for the servos. It works fine.
I was using a motor shield because initially I thought I’d be using DC motors. I switched to full rotation servos, but didn’t think to eliminate the motor shield I had in place. I guess I’d only need the motor shield if I was running bigger DC motors as the Arduino can only power tiny DC motors.
Thanks. This forum is a huge help always.

stevex: as the Arduino can only power tiny DC motors.

Best to assume an Arduino can NOT power any motors.