Powering Audrino and easydriver together

I recently started working with Audrino and I need help to make my project to work without PC USB also. So I plan to drive my audrino and a easydriver both connected to a 9 volt 2.5 amp smps in parallel. Other than the easydriver connections Audrino have a 204 I2C display and a 164 keypad attached to it. Will it be ok to use that power supply? :slight_smile: (Easydriver will be driving a Nema 17 stepper)

You need to post a link to the datasheet for your stepper motor. Nema 17 only tell us that the front face is 1.7 inches across.

Assuming you motor draws less than 750mA per coil your power supply should be OK - except that I don't know if the Easydriver can work with a voltage as low as 9v. Just check the specifications.

Stepper Motor Basics
Simple Stepper Code

I think I have ordered a 1.2 Amp/ phase stepper.

Axial Force: 10N (Max)
Configuration: Unipolar
Current/Phase: 1.2A
Rated Torque: 4.2 kg cm
Dielectric Strength: 500 VAC for 1 minute
Face Size: NEMA 17
Inductance/Phase: 3.2mH
Insulation Resistance 100 Megaohms Min. (500 VDC)
Shaft Radial Play 0.02 mm Max (450g load)
Temperature Rise [Max] 80 Degrees C
Step Angle 1.8ยฐper step
Operational Temperature Range -20/+50 Degrees C
Radial Force [Max] 28N (20mm from flange)
Resistance/Phase 3.3 Ohms
Rotor Inertia 54 g/cm2
Shaft Axial Play 0.08mm (450g load)

I think I have ordered a 1.2 Amp/ phase stepper.

An Easydriver will not be suitable for that as its maximum current is about 750mA. You will need a BigEasydriver or a Pololu A4988 (both of which use the A4988 chip) or a Pololu DRV8825.