SLVSFN2B September   2021  – February 2022 DRV8311

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 SPI Timing Requirements
    7. 7.7 SPI Secondary Device Mode Timings
    8. 7.8 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Output Stage
      2. 8.3.2  Control Modes
        1. 8.3.2.1 6x PWM Mode (DRV8311S and DRV8311H variants only)
        2. 8.3.2.2 3x PWM Mode (DRV8311S and DRV8311H variants only)
        3. 8.3.2.3 PWM Generation Mode (DRV8311S and DRV8311P Variants)
      3. 8.3.3  Device Interface Modes
        1. 8.3.3.1 Serial Peripheral Interface (SPI)
        2. 8.3.3.2 Hardware Interface
      4. 8.3.4  AVDD Linear Voltage Regulator
      5. 8.3.5  Charge Pump
      6. 8.3.6  Slew Rate Control
      7. 8.3.7  Cross Conduction (Dead Time)
      8. 8.3.8  Propagation Delay
      9. 8.3.9  Pin Diagrams
        1. 8.3.9.1 Logic Level Input Pin (Internal Pulldown)
        2. 8.3.9.2 Logic Level Input Pin (Internal Pullup)
        3. 8.3.9.3 Open Drain Pin
        4. 8.3.9.4 Push Pull Pin
        5. 8.3.9.5 Four Level Input Pin
      10. 8.3.10 Current Sense Amplifiers
        1. 8.3.10.1 Current Sense Amplifier Operation
        2. 8.3.10.2 Current Sense Amplifier Offset Correction
      11. 8.3.11 Protections
        1. 8.3.11.1 VM Supply Undervoltage Lockout (NPOR)
        2. 8.3.11.2 Under Voltage Protections (UVP)
        3. 8.3.11.3 Overcurrent Protection (OCP)
          1. 8.3.11.3.1 OCP Latched Shutdown (OCP_MODE = 010b)
          2. 8.3.11.3.2 OCP Automatic Retry (OCP_MODE = 000b or 001b)
          3. 8.3.11.3.3 OCP Report Only (OCP_MODE = 011b)
          4. 8.3.11.3.4 OCP Disabled (OCP_MODE = 111b)
        4. 8.3.11.4 Thermal Protections
          1. 8.3.11.4.1 Thermal Warning (OTW)
          2. 8.3.11.4.2 Thermal Shutdown (OTSD)
    4. 8.4 Device Functional Modes
      1. 8.4.1 Functional Modes
        1. 8.4.1.1 Sleep Mode
        2. 8.4.1.2 Operating Mode
        3. 8.4.1.3 Fault Reset (CLR_FLT or nSLEEP Reset Pulse)
    5. 8.5 SPI Communication
      1. 8.5.1 Programming
        1. 8.5.1.1 SPI and tSPI Format
  9. 9 DRV8311 Registers
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Three-Phase Brushless-DC Motor Control
        1. 10.2.1.1 Detailed Design Procedure
          1. 10.2.1.1.1 Motor Voltage
        2. 10.2.1.2 Driver Propagation Delay and Dead Time
        3. 10.2.1.3 Delay Compensation
        4. 10.2.1.4 Current Sensing and Output Filtering
        5. 10.2.1.5 Application Curves
    3. 10.3 Three Phase Brushless-DC tSPI Motor Control
      1. 10.3.1 Detailed Design Procedure
    4. 10.4 Alternate Applications
  11. 11Power Supply Recommendations
    1. 11.1 Bulk Capacitance
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Considerations
      1. 12.3.1 Power Dissipation and Junction Temperature Estimation
  13. 13Device and Documentation Support
    1. 13.1 Support Resources
    2. 13.2 Trademarks
    3. 13.3 Electrostatic Discharge Caution
    4. 13.4 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.10.2 Current Sense Amplifier Offset Correction

CSA output has an offset induced due to ground differences between the sense FET and output FET. When running trapezoidal control or another single-shunt based control (sensored sine, for example) this CSA offset has no impact to operation. When running sensorless sinusoidal or FOC control where two or three current sense are required, some current distortion and noise may occur unless the user implements the corrective action below.

Corrective Action: Implement the below equations in firmware to correct for any current induced offset:

  1. When all three current sense amplifiers are used:
    Equation 3. i a =   1.001152 * i a _ s e n s e d     - 0.003375 * i b _ s e n s e d     - 0.003103 * i c _ s e n s e d
    Equation 4. i b =   0.002369 * i a s e n s e d   + 1.000665 * i b _ s e n s e d     - 0.019126 * i c _ s e n s e d
    Equation 5. i c =   0.001234 * i a s e n s e d +   0.001595 * i b s e n s e d   + 0.998166 * i c _ s e n s e d
  2. When only two of the three current sense amplifiers are used:
    1. Current sensed in phases A & B:
      Equation 6. i a =   1.004346 * i a _ s e n s e d     - 0.000199 * i b _ s e n s e d
      Equation 7. i b = 0.022060 * i a s e n s e d   + 1.020405 * i b _ s e n s e d
      Equation 8. i c = - i a + i b
    2. Current sensed in phases B & C:
      Equation 9. i b =   0.998309 * i b _ s e n s e d     - 0.021427 * i c _ s e n s e d
      Equation 10. i c =   0.000368 * i b s e n s e d   + 0.996967 * i c _ s e n s e d
      Equation 11. i a = - i b + i c
    3. Current sensed in phases C & A
      Equation 12. i a =   1.004547 * i a s e n s e d   + 0.000195 * i c _ s e n s e d
      Equation 13. i c =   0.000371 * i a s e n s e d + 0.996975 * i c _ s e n s e d
      Equation 14. i b = - i a + i c