SLOA312 December   2021 DRV8412 , DRV8424 , DRV8426 , DRV8428 , DRV8434 , DRV8436 , DRV8803 , DRV8804 , DRV8805 , DRV8806 , DRV8844 , DRV8847 , DRV8932 , DRV8935 , DRV8955

PRODUCTION DATA  

  1.   Trademarks
  2. 1Introduction
  3. 2Principle of Operation
    1. 2.1 Unipolar Stepper Motors
    2. 2.2 Bipolar Stepper Motors
  4. 3How to Drive Unipolar Stepper Motors with DRV8xxx Drivers
    1. 3.1 Driving Unipolar Motor with Four-channel Low-side Driver
    2. 3.2 Driving a Unipolar Motor with a Bipolar Driver
    3. 3.3 Driving Unipolar Motor with Four-channel Half-Bridge Driver
      1. 3.3.1 Driving in Full-step Mode
        1. 3.3.1.1 Full-step Mode with One Phase ON
        2. 3.3.1.2 Two Phases ON
      2. 3.3.2 Driving in Half-step Mode
      3. 3.3.3 Example Pseudocode
        1. 3.3.3.1 Code for Full-step with One Phase ON
        2. 3.3.3.2 Code for Full-step with Two Phase ON
        3. 3.3.3.3 Code for Half-step
  5. 4References

2.2 Bipolar Stepper Motors

Bipolar stepper motors have only a single winding per phase. Four wires are connected to the motor windings, and there is no center tap to VM.

GUID-B0A4E3B4-9C19-424C-A84A-B821D77C557F-low.jpgFigure 2-2 Bipolar Stepper Motor

Bipolar steppers require more complicated driver electronics (typically an H-bridge for each phase) to be able to reverse the current in the winding. However, bipolar drivers use the full amount of copper windings, so the motor delivers more torque.