RC servo - need driver for control signal?

Forum 2005-2010 (read only) Hardware Interfacing
1

Does anyone have an idea how much current is drawn by the control signal of a (Graupner C677) RC servo?

I want to control the servo with Arduino (obviously). Power and GND will come from the boards power supply, but I wonder if I need something like a ULN2803 for the servo's control signal.

2

I've never yet come across a case where the control to a servo needs beefing-up - just connect straight to the Arduino.
But always try to provide a separate power supply for the servo - don't depend on the Arduino's regulator.

3

Thanks, AWOL. It's what I suspected.

The servo will not be powered from the Arduino's supply, that teenie tiny regulator isn't going to handle a couple of hundred mAmps gracefully.

The project will probably get powered by a 9V battery, conencted directly to the Arduino and through a 7805 to the servo.