SLVSHE3 June   2024 DRV2911-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings Auto
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Output Stage
      2. 6.3.2 Hardware Interface
      3. 6.3.3 AVDD Linear Voltage Regulator
      4. 6.3.4 Step-Down Mixed-Mode Buck Regulator
        1. 6.3.4.1 Buck in Inductor Mode
        2. 6.3.4.2 Buck in Resistor mode
        3. 6.3.4.3 Buck Regulator with External LDO
        4. 6.3.4.4 AVDD Power Sequencing with Buck Regulator
        5. 6.3.4.5 Mixed mode Buck Operation and Control
        6. 6.3.4.6 Buck Undervoltage Lockout
        7. 6.3.4.7 Buck Overcurrent Protection
      5. 6.3.5 Charge Pump
      6. 6.3.6 Slew Rate Control
      7. 6.3.7 Cross Conduction (Dead Time)
      8. 6.3.8 Propagation Delay
      9. 6.3.9 Protections
        1. 6.3.9.1 PVDD Supply Undervoltage Lockout
        2. 6.3.9.2 AVDD Undervoltage Lockout
        3. 6.3.9.3 VCP Charge Pump Undervoltage Lockout
        4. 6.3.9.4 Overcurrent Latched Protection
        5. 6.3.9.5 Thermal Shutdown (OTSD)
          1. 6.3.9.5.1 OTSD FET
          2. 6.3.9.5.2 OTSD (Non-FET)
    4. 6.4 Device Functional Modes
      1. 6.4.1 Functional Modes
        1. 6.4.1.1 Reset Mode
        2. 6.4.1.2 Operating Mode
        3. 6.4.1.3 Fault Reset (RESETZ Pulse)
      2. 6.4.2 OUTOFF functionality
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Design Procedure
      2. 7.2.2 Voltage and Current Sense Circuitry
  9. 8 Power Supply Recommendations
    1. 8.1 Bulk Capacitance
  10. 9 Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
    3. 9.3 Thermal Considerations
      1. 9.3.1 Power Dissipation
  11. 10Device and Documentation Support
    1. 10.1 Third-Party Products Disclaimer
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information

Package Options

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

8.1 Bulk Capacitance

Having an appropriate local bulk capacitance is an important factor in optimal driver performance. 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 system
  • The capacitance and current capability of the power supply
  • The amount of parasitic inductance between the power supply and load
  • The acceptable voltage ripple

The inductance between the power supply and the drive system limits the rate that current can change from the power supply. If the local bulk capacitance is too small, the system responds to excessive current demands with a change in voltage. When adequate bulk capacitance is used, the output voltage remains stable, and a 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.

DRV2911-Q1 Example Setup of ULC Driver System With External Power SupplyFigure 8-1 Example Setup of ULC Driver System With External Power Supply

The voltage rating for bulk capacitors should be higher than the operating voltage, to provide margin for optimal driver performance.