SLOSE48 December   2020 DRV8434A

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1. 5.1 Pin 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
      1. 6.6.1 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 and Decay Mode
        1. 7.3.5.1 Smart tune Ripple Control
        2. 7.3.5.2 Blanking Time
      6. 7.3.6 Charge Pump
      7. 7.3.7 Linear Voltage Regulators
      8. 7.3.8 Logic Level, tri-level and quad-level Pin Diagrams
        1. 7.3.8.1 nFAULT Pin
      9. 7.3.9 Protection Circuits
        1. 7.3.9.1 VM Undervoltage Lockout (UVLO)
        2. 7.3.9.2 VCP Undervoltage Lockout (CPUV)
        3. 7.3.9.3 Overcurrent Protection (OCP)
        4. 7.3.9.4 Stall Detection
        5. 7.3.9.5 Open-Load Detection (OL)
        6. 7.3.9.6 Thermal Shutdown (OTSD)
        7.       Fault Condition Summary
    4. 7.4 Device Functional Modes
      1. 7.4.1 Sleep Mode (nSLEEP = 0)
      2.      43
      3. 7.4.2 Disable Mode (nSLEEP = 1, ENABLE = 0)
      4. 7.4.3 Operating Mode (nSLEEP = 1, ENABLE = Hi-Z/1)
      5. 7.4.4 nSLEEP Reset Pulse
      6.      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 Mode
        4. 8.2.2.4 Application Curves
        5. 8.2.2.5 Thermal Application
          1. 8.2.2.5.1 Power Dissipation
          2. 8.2.2.5.2 Conduction Loss
          3. 8.2.2.5.3 Switching Loss
          4. 8.2.2.5.4 Power Dissipation Due to Quiescent Current
          5. 8.2.2.5.5 Total Power Dissipation
          6. 8.2.2.5.6 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 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.4 Controlling VREF with an MCU DAC

In some cases, the full-scale output current may need to be changed between many different values, depending on motor speed and loading. The voltage of the VREF pin can be adjusted in the system to change the full-scale current.

In this mode of operation, as the DAC voltage increases, the full-scale regulation current increases as well. For proper operation, the output of the DAC must not exceed 3.3 V.

GUID-05558481-CF23-4D3D-8720-A998E2DE150D-low.gifFigure 7-3 Controlling VREF with a DAC Resource

The VREF pin can also be adjusted using a PWM signal and low-pass filter.

GUID-7D9A793D-81B1-43A8-BC42-7AA694E61F99-low.gifFigure 7-4 Controlling VREF With a PWM Resource