SLVSHB1A March   2023  – November 2024 DRV8329-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specification
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings Auto
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information 2pkg
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Three BLDC Gate Drivers
        1. 7.3.1.1 PWM Control Modes
          1. 7.3.1.1.1 6x PWM Mode
          2. 7.3.1.1.2 3x PWM Mode
        2. 7.3.1.2 Device Hardware Interface
        3. 7.3.1.3 Gate Drive Architecture
          1. 7.3.1.3.1 Propagation Delay
          2. 7.3.1.3.2 Deadtime and Cross-Conduction Prevention
      2. 7.3.2 AVDD Linear Voltage Regulator
      3. 7.3.3 Pin Diagrams
      4. 7.3.4 Low-Side Current Sense Amplifiers
        1. 7.3.4.1 Current Sense Operation
      5. 7.3.5 Gate Driver Shutdown Sequence (DRVOFF)
      6. 7.3.6 Gate Driver Protective Circuits
        1. 7.3.6.1 PVDD Supply Undervoltage Lockout (PVDD_UV)
        2. 7.3.6.2 AVDD Power on Reset (AVDD_POR)
        3. 7.3.6.3 GVDD Undervoltage Lockout (GVDD_UV)
        4. 7.3.6.4 BST Undervoltage Lockout (BST_UV)
        5. 7.3.6.5 MOSFET VDS Overcurrent Protection (VDS_OCP)
        6. 7.3.6.6 VSENSE Overcurrent Protection (SEN_OCP)
        7. 7.3.6.7 Thermal Shutdown (OTSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Gate Driver Functional Modes
        1. 7.4.1.1 Sleep Mode
        2. 7.4.1.2 Operating Mode
        3. 7.4.1.3 Fault Reset (nSLEEP Reset Pulse)
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Three Phase Brushless-DC Motor Control
        1. 8.2.1.1 Detailed Design Procedure
          1. 8.2.1.1.1  Motor Voltage
          2. 8.2.1.1.2  Bootstrap Capacitor and GVDD Capacitor Selection
          3. 8.2.1.1.3  Gate Drive Current
          4. 8.2.1.1.4  Gate Resistor Selection
          5. 8.2.1.1.5  System Considerations in High Power Designs
            1. 8.2.1.1.5.1 Capacitor Voltage Ratings
            2. 8.2.1.1.5.2 External Power Stage Components
            3. 8.2.1.1.5.3 Parallel MOSFET Configuration
          6. 8.2.1.1.6  Dead Time Resistor Selection
          7. 8.2.1.1.7  VDSLVL Selection
          8. 8.2.1.1.8  AVDD Power Losses
          9. 8.2.1.1.9  Current Sensing and Output Filtering
          10. 8.2.1.1.10 Power Dissipation and Junction Temperature Losses
      2. 8.2.2 Application Curves
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Bulk Capacitance Sizing
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Thermal Considerations
        1. 8.4.2.1 Power Dissipation
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Related Links
    4. 9.4 Receiving Notification of Documentation Updates
    5. 9.5 Community Resources
    6. 9.6 Trademarks
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
8.2.1.1.3 Gate Drive Current

Selecting an appropriate gate drive current is essential when turning on or off power MOSFETs gates to switch motor current. The amount of gate drive current and input capacitance of the MOSFETs determines the drain-to-source voltage slew rate (VDS). Gate drive current can be sourced from GVDD into the MOSFET gate (ISOURCE) or sunk from the MOSFET gate into SHx or LSS (ISINK).

Using too high of a gate drive current can turn on MOSFETs too quickly which may cause excessive ringing, dV/dt coupling, or cross-conduction from switching large amounts of current. If parasitic inductances and capacitances exist in the system, voltage spiking or ringing may occur which can damage the MOSFETs or DRV8329-Q1 device.

DRV8329-Q1 Effects of high gate drive currentFigure 8-2 Effects of high gate drive current

On the other hand, using too low of a gate drive current causes long VDS slew rates. Turning on the MOSFETs too slowly may heat up the MOSFETs due to RDS,on switching losses.

The relationship between gate drive current IGATE, MOSFET gate-to-drain charge QGD, and VDS slew rate switching time trise,fall are described by the following equations:

Equation 8. SRDS=VDStrise,fall
Equation 9. IGATE=Qgdtrise,fall

It is recommend to evaluate at lower gate drive currents and increase gate drive current settings to avoid damage from unintended operation during initial evaluation.