SLVS855K July   2008  – March 2021 DRV8800 , DRV8801

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Typical Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1  Logic Inputs
      2. 8.3.2  VREG (DRV8800 Only)
      3. 8.3.3  VPROPI (DRV8801 Only)
        1. 8.3.3.1 Connecting VPROPI Output to ADC
      4. 8.3.4  Charge Pump
      5. 8.3.5  Shutdown
      6. 8.3.6  Low-Power Mode
      7. 8.3.7  Braking
      8. 8.3.8  Diagnostic Output
      9. 8.3.9  Thermal Shutdown (TSD)
      10. 8.3.10 Overcurrent Protection
      11. 8.3.11 SENSE
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Operation
        1. 8.4.1.1 Slow-Decay SR (Brake Mode)
        2. 8.4.1.2 Fast Decay With Synchronous Rectification
          1. 8.4.1.2.1 34
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Motor Voltage
        2. 9.2.2.2 Power Dissipation
        3. 9.2.2.3 Thermal Considerations
          1. 9.2.2.3.1 Junction-to-Ambiant Thermal Impedance (ƟJA)
        4. 9.2.2.4 Motor Current Trip Point
        5. 9.2.2.5 Sense Resistor Selection
        6. 9.2.2.6 Drive Current
      3. 9.2.3 Pulse-Width Modulating
        1. 9.2.3.1 Pulse-Width Modulating ENABLE
        2. 9.2.3.2 Pulse-Width Modulating PHASE
      4. 9.2.4 Application Curves
    3. 9.3 Parallel Configuration
      1. 9.3.1 Parallel Connections
      2. 9.3.2 Non – Parallel Connections
      3. 9.3.3 Wiring nFAULT as Wired OR
      4. 9.3.4 Electrical Considerations
        1. 9.3.4.1 Device Spacing
        2. 9.3.4.2 Recirculation Current Handling
        3. 9.3.4.3 Sense Resistor Selection
        4. 9.3.4.4 Maximum System Current
  10. 10Power Supply Recommendations
    1. 10.1 Bulk Capacitance
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Related Links
    2. 12.2 Trademarks
    3. 12.3 Electrostatic Discharge Caution
    4. 12.4 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.4 Motor Current Trip Point

When the voltage on pin SENSE exceeds VTRP (0.5 V), overcurrent is detected. The RSENSE resistor should be sized to set the desired ITRIP level.

Equation 6. RSENSE = 0.5 V / ITRIP

To set ITRIP to 2.5 A, RSENSE = 0.5 V / 2.5 A = 0.2 Ω.

To prevent false trips, ITRIP must be higher than regular operating current. Motor current during startup is typically much higher than steady-state spinning, because the initial load torque is higher, and the absence of back-EMF causes a higher voltage and extra current across the motor windings.

It can be beneficial to limit startup current by using series inductors on the DRV880x output, as that allows ITRIP to be lower, and it may decrease the system’s required bulk capacitance. Startup current can also be limited by ramping the forward drive duty cycle.