SLOSE70 December   2020 DRV8434S

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 SPI Timing Requirements
    7. 6.7 Indexer Timing Requirements
      1. 6.7.1 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
      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 Slow Decay for Increasing Current, Fast Decay for Decreasing current
        4. 7.3.6.4 Mixed Decay for Increasing and Decreasing Current
        5. 7.3.6.5 Smart tune Dynamic Decay
        6. 7.3.6.6 Smart tune Ripple Control
      7. 7.3.7  PWM OFF Time
      8. 7.3.8  Blanking time
      9. 7.3.9  Charge Pump
      10. 7.3.10 Linear Voltage Regulators
      11. 7.3.11 Logic Level, tri-level and quad-level Pin Diagrams
        1. 7.3.11.1 nFAULT Pin
      12. 7.3.12 Protection Circuits
        1. 7.3.12.1 VM Undervoltage Lockout (UVLO)
        2. 7.3.12.2 VCP Undervoltage Lockout (CPUV)
        3. 7.3.12.3 Overcurrent Protection (OCP)
          1. 7.3.12.3.1 Latched Shutdown (OCP_MODE = 0b)
          2. 7.3.12.3.2 Automatic Retry (OCP_MODE = 1b)
        4. 7.3.12.4 Stall Detection
        5. 7.3.12.5 Open-Load Detection (OL)
        6. 7.3.12.6 Overtemperature Warning (OTW)
        7. 7.3.12.7 Thermal Shutdown (OTSD)
          1. 7.3.12.7.1 Latched Shutdown (OTSD_MODE = 0b)
          2. 7.3.12.7.2 Automatic Recovery (OTSD_MODE = 1b)
        8.       Fault Condition Summary
    4. 7.4 Device Functional Modes
      1. 7.4.1 Sleep Mode (nSLEEP = 0)
      2.      56
      3. 7.4.2 Disable Mode (nSLEEP = 1, ENABLE = 0)
      4. 7.4.3 Operating Mode (nSLEEP = 1, ENABLE = 1)
      5. 7.4.4 nSLEEP Reset Pulse
      6.      Functional Modes Summary
    5. 7.5 Programming
      1. 7.5.1 Serial Peripheral Interface (SPI) Communication
        1. 7.5.1.1 SPI Format
        2. 7.5.1.2 SPI for a Single Target Device
        3. 7.5.1.3 SPI for Multiple Target Devices in Daisy Chain Configuration
        4. 7.5.1.4 SPI for Multiple Target Devices in Parallel Configuration
    6. 7.6 Register Maps
  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
      1. 10.1.1 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

3 Description

The DRV8434S is a stepper motor driver for industrial and consumer applications. The device is fully integrated with two N-channel power MOSFET H-bridge drivers, a microstepping indexer, and integrated current sensing. The DRV8434S is capable of driving up to 2.5-A full-scale output current (dependent on PCB design).

The DRV8434S uses an internal current sense architecture to eliminate the need for two external power sense resistors, saving PCB area and system cost. The device uses an internal PWM current regulation scheme selectable between smart tune, slow and mixed decay options. Smart tune automatically adjusts for optimal current regulation and reduces audible noise from the motor.

A simple SPI interface with STEP/DIR pins allows an external controller to manage the direction and step rate of the stepper motor. The device can be configured in full-step to 1/256 microstepping. With advanced stall detection algorithm, designers can detect if the motor stopped and take action as needed. The device also includes an integrated torque DAC which allows scaling the output current through SPI without needing to scale the VREF reference. Other protection features are provided for supply undervoltage, charge pump faults, overcurrent, short circuits, open load, and overtemperature. Fault conditions are indicated by the nFAULT pin.

A low-power sleep mode is provided for very low standby current using an nSLEEP pin. The device features full duplex, 4-wire synchronous SPI communication, with daisy chain support for up to 63 devices connected in series, for configurability and detailed fault reporting.

Device Information
PART NUMBER (1)PACKAGEBODY SIZE (NOM)
DRV8434SPWPRHTSSOP (28)9.7mm x 4.4mm
DRV8434SRGERVQFN (24)4mm x 4mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.
GUID-5BB1577A-8DC3-4E48-B1BE-752E6530F8A8-low.jpgSimplified Schematic