For this tutorial you will need the following:
2x DRV8871 Breakout Boards
Each DRV8871 breakout board contains a single H-bridge. Since the stepper motor has 2 sets of windings, we will need two of them: One DRV8871 for each winding.
We are using a full-size board here. But the circuit would fit on a half-size breadboard just as well.
A Stepper Motor
In the example circuit, we are using a bipolar stepper with the following specs:
- NEMA 17
- Torque: 76 oz-in - 5.47 kg-cm
- Step Angle: 1.8
- Winding Resistance: 1.8 Ohms/Phase
- DC 2 A/Phase
- 12-24VDC (Recommended)
But this tutorial will work with many NEMA-17 and NEMA-23 bipolar stepper motors -including the NEMA-17 motor from our store.
A Power Supply
We are using a 12v/5A supply in our example circuit.
Using our example motor with a 1.8 ohm phase resistance, this would draw 6.7A per phase and would quickly burn out a V1 or V2 motor shield.
But the DRV8871 breakout is configured to automatically limit the current to a maximum of 2A. This is a safe level for both the motor and the driver.