SLVSI22 August   2025 DRV8844A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Output Stage
      2. 6.3.2 Logic Inputs
      3. 6.3.3 Bridge Control
      4. 6.3.4 Charge Pump
      5. 6.3.5 Protection Circuits
        1. 6.3.5.1 Overcurrent Protection (OCP)
        2. 6.3.5.2 Thermal Shutdown (TSD)
        3. 6.3.5.3 Undervoltage Lockout (UVLO)
      6. 6.3.6 CLR_FAULT and nSLEEP Operation
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Application Information
      1. 7.2.1 Driving Solenoid Loads
      2. 7.2.2 Driving Stepper Motor
      3. 7.2.3 Driving Brushed DC motor
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Bulk Capacitance
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Thermal Considerations
        1. 7.4.3.1 Heatsinking
      4. 7.4.4 Power Dissipation
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
      1. 8.1.1 Related Documentation
    2. 8.2 Community Resources
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.2.2 Driving Stepper Motor

The DRV8844A can drive one stepper motor using the PWM input interface.

DRV8844A DRV8844A Used to Drive a Stepper Motor Figure 7-4 DRV8844A Used to Drive a Stepper Motor

DRV8844A allows user to connect current sense resistor for each individual half bridge for Stepper motor current regulation control

The full-scale current (IFS) is the maximum current driven through either winding. The DRV8844A allows the connection of current sense resistors on the Source terminals of all 4 Half bridges which enables true bidirectional current sense needed in motor control applications. Additionally the on board 3.3V LDO can be used to provide a reference voltage for current regulation.

Note: The IFS current must also follow given equation so as to avoid saturating the motor. VM is the motor supply voltage, and RL is the motor winding resistance.
Equation 1. DRV8844A

If the target motor speed is too high, the motor does not spin. Make sure that the motor can support the target speed.

For a desired motor speed (v), microstepping level (nm), and motor full step angle (θstep), determine the frequency of the input waveform as follows -

Equation 2. DRV8844A

θstep can be found in the stepper motor data sheet or written on the motor.

The frequency ƒstep gives the frequency of input change on the DRV8962. 1/ ƒstep = tSTEP on the diagram below. shows an example calculation for a 120 rpm target speed and 1/2 step.

Equation 3. DRV8844A
DRV8844A Example 1/2 Stepping Operation Figure 7-5 Example 1/2 Stepping Operation