SLVS855J July   2008  – March 2015 DRV8800 , DRV8801

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Simplified Schematic
  5. Revision History
  6. Pin Configuration and Functions
  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 Typical Characteristics
  8. Parameter Measurement Information
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagrams
    3. 9.3 Feature Description
      1. 9.3.1  Logic Inputs
      2. 9.3.2  VREG (DRV8800 Only)
      3. 9.3.3  VPROPI (DRV8801 Only)
      4. 9.3.4  Charge Pump
      5. 9.3.5  Shutdown
      6. 9.3.6  Low-Power Mode
      7. 9.3.7  Braking
      8. 9.3.8  Diagnostic Output
      9. 9.3.9  Thermal Shutdown (TSD)
      10. 9.3.10 Overcurrent Protection
      11. 9.3.11 SENSE
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device Operation
        1. 9.4.1.1 Slow-Decay SR (Brake Mode)
        2. 9.4.1.2 Fast Decay With Synchronous Rectification
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Motor Voltage
        2. 10.2.2.2 Power Dissipation
        3. 10.2.2.3 Motor Current Trip Point
        4. 10.2.2.4 Sense Resistor Selection
        5. 10.2.2.5 Drive Current
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
    1. 11.1 Bulk Capacitance
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Related Links
    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

11 Power Supply Recommendations

11.1 Bulk Capacitance

Having appropriate local bulk capacitance is an important factor in motor drive system design. It is generally beneficial to have more bulk capacitance, while the disadvantages are increased cost and physical size.

The amount of local capacitance needed depends on a variety of factors, including:

  • The highest current required by the motor system.
  • The capacitance of the power supply and its ability to source current.
  • The amount of parasitic inductance between the power supply and motor systems.
  • The acceptable voltage ripple.
  • The type of motor used (Brushed DC, Brushless DC, Stepper).
  • The motor braking method.

The inductance between the power supply and motor drive system will limit the rate current can change from the power supply. If the local bulk capacitance is too small, the system will respond to excessive current demands or dumps from the motor with a change in voltage. When adequate bulk capacitance is used, the motor voltage remains stable and high current can be quickly supplied.

The data sheet generally provides a recommended value, but system-level testing is required to determine the appropriate sized bulk capacitor.

DRV8800 DRV8801 bulk.gifFigure 16. Example Setup of Motor Drive System With External Power Supply