Controlling Stepper Motor with Arduino and HBridge SN754410NE

Hi everyone,

I am trying to control a stepper servo ASTROSYN - MY7001 - STEPPER MOTOR, 14, 20MM with an Arduino Uno and the HBridge SN754410NE as shown on the page:

It works fine with a 9v battery connected to the breadboard, although the battery dies in a little time. That's why I have some doubts and questions re the power that I need to supply to the motor. So far I haven't been able to guess the amount of power requested from the datasheets

I have shown the datasheet to some helpful sop assistants at Maplin but they couldn't figure that out. After that I have spoken to Astrosyn, the makers of the motor, only to find out I should buy a P300 driver (input 18-36v) to control the motor (cost 54£), although I mentioned I was using Arduino to control it; they suggested I get in touch with the makers of the board (Arduino) and ask the same question.

My question is: - what type of ac-dc adaptor should I use to power the HBridge driver to control the Stepper Motor? - has anyone had the same (or similar) experience?

Many many thanks in advance for your time and help

I wish you all a very good day



The windings are 44 ohm and take a max of 0.4A. At 9V they'll take 200mA, far beyond the capabilities of a PP3 9V battery. The motor will work upto 18V supply.

If you use wave-drive you'll power one winding at a time (200mA at 9V, 270mA at 12V), if half-stepping or full-stepping its twice that.

You need a power supply good for those current levels in the first instance.

If you run at lower voltages than 18V you'll get lower winding currents and hence lower torque, note - this may be fine, depends how much torque you want. Note that at 18V it will get HOT. 12V might be more reasonable.

Because the windings are high inductance it won't step really fast, even with high voltage drive - look for motors with low winding resistance/inductance if you want high RPM's - you will then need a PWM bipolar driver like the one you mention (check and others for cheaper options though). This motor isn't going to benefit from a PWM driver though I think.

Wow MarkT,

that's just everything I needed to know!!!! I will give it a go in a minute, I have a 12V adaptor with me which should be suitable for the job.

have a very good day and again thanks for your help!