SLVSDA5E January   2016  – March 2020 DRV8884

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      Microstepping Current Waveform
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    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
    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  Current Regulation
      5. 7.3.5  Controlling RREF With an MCU DAC
        1. 7.3.5.1 Various Sources of Error
          1. 7.3.5.1.1 VRREF, ARREF, and RREF Error
          2. 7.3.5.1.2 VDAC Error
        2. 7.3.5.2 Application-Specific Error Calculations
      6. 7.3.6  Decay Modes
        1. 7.3.6.1 Mode 1: Slow Decay for Increasing and Decreasing Current
        2. 7.3.6.2 Mode 2: Slow Decay for Increasing Current, Mixed Decay for Decreasing Current
        3. 7.3.6.3 Mode 3: Mixed Decay for Increasing and Decreasing Current
      7. 7.3.7  Blanking Time
      8. 7.3.8  Charge Pump
      9. 7.3.9  LDO Voltage Regulator
      10. 7.3.10 Logic and Multi-Level Pin Diagrams
      11. 7.3.11 Protection Circuits
        1. 7.3.11.1 VM UVLO
        2. 7.3.11.2 VCP Undervoltage Lockout (CPUV)
        3. 7.3.11.3 Overcurrent Protection (OCP)
        4. 7.3.11.4 Thermal Shutdown (TSD)
    4. 7.4 Device Functional Modes
  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
  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 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.1 Overview

The DRV8884 is an integrated motor driver solution for bipolar stepper motors. The device integrates two NMOS H-bridges, integrated current sense and regulation circuitry, and a microstepping indexer. The DRV8884 can be powered with a supply voltage between 8 and 37 V, and is capable of providing an output current with up to 1.7-A peak, 1.0-A full-scale, or 0.7-A rms. Actual full-scale and rms current depends on ambient temperature, supply voltage, and PCB ground plane size.

The DRV8884 integrates current sense functionality, which eliminates the need for high-power external sense resistors. This integration does not dissipate the external sense resistor power, because the current sense functionality is not implemented using a resistor-based architecture. This functionality helps improve component cost, board size, PCB layout, and system power consumption.

A simple STEP/DIR interface allows easy interfacing to the controller circuit. The internal indexer is able to execute high-accuracy microstepping without requiring the processor to control the current level. The indexer is capable of full step and half step as well as microstepping to 1/4, 1/8, and 1/16. In addition to the standard half-stepping mode, a non-circular 1/2-stepping mode is available for increased torque output at higher motor rpm.

The current regulation is configurable with several decay modes of operation. The decay mode can be selected as a fixed slow, slow/mixed, or mixed decay. The slow/mixed decay mode uses slow decay on increasing steps and mixed decay on decreasing steps.

An adaptive blanking time feature automatically scales the minimum drive time with output current. This helps alleviate zero-crossing distortion by limiting the drive time at low-current steps.

A torque DAC feature allows the controller to scale the output current without needing to scale the reference resistor. The torque DAC is accessed using a digital input pin. This allows the controller to save power by decreasing the current consumption when not high current is not required.

A low-power sleep mode is included that allows the system to save power when not driving the motor.