SLOSE59C May   2020  – July 2022 DRV8424 , DRV8425

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
    1.     Device Comparison Table
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Indexer Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Stepper Motor Driver Current Ratings
        1. 7.3.1.1 Peak Current Rating
        2. 7.3.1.2 RMS Current Rating
        3. 7.3.1.3 Full-Scale Current Rating
      2. 7.3.2  PWM Motor Drivers
      3. 7.3.3  Microstepping Indexer
      4. 7.3.4  Controlling VREF with an MCU DAC
      5. 7.3.5  Current Regulation
      6. 7.3.6  Decay Modes
        1. 7.3.6.1 Slow Decay for Increasing and Decreasing Current
        2. 7.3.6.2 Slow Decay for Increasing Current, Mixed Decay for Decreasing Current
        3. 7.3.6.3 Mixed Decay for Increasing and Decreasing Current
        4. 7.3.6.4 Smart tune Dynamic Decay
        5. 7.3.6.5 Smart tune Ripple Control
        6. 7.3.6.6 PWM OFF Time
        7. 7.3.6.7 Blanking time
      7. 7.3.7  Charge Pump
      8. 7.3.8  Linear Voltage Regulators
      9. 7.3.9  Logic Level, tri-level and quad-level Pin Diagrams
      10. 7.3.10 nFAULT Pin
      11. 7.3.11 Protection Circuits
        1. 7.3.11.1 VM Undervoltage Lockout (UVLO)
        2. 7.3.11.2 VCP Undervoltage Lockout (CPUV)
        3. 7.3.11.3 Overcurrent Protection (OCP)
          1. 7.3.11.3.1 Latched Shutdown
          2. 7.3.11.3.2 Automatic Retry
        4. 7.3.11.4 Thermal Shutdown (OTSD)
          1. 7.3.11.4.1 Latched Shutdown
          2. 7.3.11.4.2 Automatic Retry
        5. 7.3.11.5 Fault Condition Summary
    4. 7.4 Device Functional Modes
      1. 7.4.1 Sleep Mode (nSLEEP = 0)
      2. 7.4.2 Disable Mode (nSLEEP = 1, ENABLE = 0)
      3. 7.4.3 Operating Mode (nSLEEP = 1, ENABLE = Hi-Z/1)
      4. 7.4.4 nSLEEP Reset Pulse
      5. 7.4.5 Functional Modes Summary
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Stepper Motor Speed
        2. 8.2.2.2 Current Regulation
        3. 8.2.2.3 Decay Modes
      3. 8.2.3 Application Curves
      4. 8.2.4 Thermal Application
        1. 8.2.4.1 Power Dissipation
          1. 8.2.4.1.1 Conduction Loss
          2. 8.2.4.1.2 Switching Loss
          3. 8.2.4.1.3 Power Dissipation Due to Quiescent Current
          4. 8.2.4.1.4 Total Power Dissipation
        2. 8.2.4.2 Device Junction Temperature Estimation
  9. 9 Power Supply Recommendations
    1. 9.1 Bulk Capacitance
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Related Links
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.6.2 Slow Decay for Increasing Current, Mixed Decay for Decreasing Current

GUID-E3B4142F-041B-4DB3-A552-D87B9A5A778B-low.gifFigure 7-10 Slow-Mixed Decay Mode

Mixed decay begins as fast decay for a time, followed by slow decay for the remainder of the tOFF time. In this mode, mixed decay only occurs during decreasing current. Slow decay is used for increasing current.

This mode exhibits the same current ripple as slow decay for increasing current, because for increasing current, only slow decay is used. For decreasing current, the ripple is larger than slow decay, but smaller than fast decay. On decreasing current steps, mixed decay settles to the new ITRIP level faster than slow decay.