Control Servo with Arduino Due

Using Arduino Motors, Mechanics, Power and CNC
#1

Hello,

I just bought some of the following servos:

TowerPro SG90 9g
(http://www.servodatabase.com/servo/towerpro/sg90)

And I would like to control about 5 of them via an Arduino Due.
While on some websites/datasheets the operating-voltage is valued by 4.8V,
there are several other shops writing, it's 3.0V to 7.0V, or 3.5V to 7.0V.

Because of the operating-voltage of the Due (3.3V) I am wondering, which of the statements is right,
so will I be able to control them via 3.3V digital signals or do I need level-converters or sth. else?

And btw., can I power them by 5V, but send signals of another voltage like 3.3V to the data-pin, or must power-voltage and signal-voltage be the same?

And what difference will it make, how much voltage I apply to power/control them?

Thanks!

#2

Nathax:
Hello,

I just bought some of the following servos:

TowerPro SG90 9g
(http://www.servodatabase.com/servo/towerpro/sg90)

And I would like to control about 5 of them via an Arduino Due.
While on some websites/datasheets the operating-voltage is valued by 4.8V,
there are several other shops writing, it's 3.0V to 7.0V, or 3.5V to 7.0V.

Because of the operating-voltage of the Due (3.3V) I am wondering, which of the statements is right,
so will I be able to control them via 3.3V digital signals or do I need level-converters or sth. else?

And btw., can I power them by 5V, but send signals of another voltage like 3.3V to the data-pin, or must power-voltage and signal-voltage be the same?

And what difference will it make, how much voltage I apply to power/control them?

Thanks!

The servo signal line should run fine on 3.3V. That is the DUE PWM output. All modern hobby servos are like that.

The servo V+ line and the DUE VCC (3.3V) should be completely separated. Servos typically are speced at 4.8 and 6 but I believe they will handle 7V.

It makes sense to run servos at a higher voltage if you are not running them flat out. They will be more efficient with the higher EMF as they can run lower on the torque/speed curve (more like a straight line). Servos are terribly inefficient near their stall torque rating and that should be avoided.

#3

So they will work fine,
if I just connect each data-pin of a servo to a digital (3.3V logic) pin of my Arduino Due
and power each servo with external 5V?

#4

Nathax:
So they will work fine,
if I just connect each data-pin of a servo to a digital (3.3V logic) pin of my Arduino Due
and power each servo with external 5V?

yes

just tie the grounds together

#5