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

3.3.2 Driving in Half-step Mode

The truth table for this mode of operation is shown in Table 3-6.

Table 3-6 Truth Table
INDEX IN1 IN2 IN3 IN4
1 0 1 1 1
2 0 0 1 1
3 1 0 1 1
4 1 0 0 1
5 1 1 0 1
6 1 1 0 0
7 1 1 1 0
8 0 1 1 0
9 0 1 1 1
10 0 0 1 1
11 1 0 1 1
12 1 0 0 1
13 1 1 0 1
14 1 1 0 0
15 1 1 1 0
16 0 1 1 0

Figure 3-10 and Figure 3-11 show the input and output waveforms when driving a unipolar stepper motor in half step mode with the DRV8935.

GUID-61449224-B6D9-485D-A0B8-82B201015CEA-low.png Figure 3-10 Input PWM signal of DRV8935
GUID-17F895C5-9C4B-43AD-9A72-6554139E94BA-low.png Figure 3-11 Output node waveforms of DRV8935