SNOSD97D October   2020  – February 2024 LMG3522R030-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
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Switching Characteristics
    7. 5.7 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Switching Parameters
      1. 6.1.1 Turn-On Times
      2. 6.1.2 Turn-Off Times
      3. 6.1.3 Drain-Source Turn-On Slew Rate
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  GaN FET Operation Definitions
      2. 7.3.2  Direct-Drive GaN Architecture
      3. 7.3.3  Drain-Source Voltage Capability
      4. 7.3.4  Internal Buck-Boost DC-DC Converter
      5. 7.3.5  VDD Bias Supply
      6. 7.3.6  Auxiliary LDO
      7. 7.3.7  Fault Detection
        1. 7.3.7.1 Overcurrent Protection and Short-Circuit Protection
        2. 7.3.7.2 Overtemperature Shutdown
        3. 7.3.7.3 UVLO Protection
        4. 7.3.7.4 Fault Reporting
      8. 7.3.8  Drive-Strength Adjustment
      9. 7.3.9  Temperature-Sensing Output
      10. 7.3.10 Ideal-Diode Mode Operation
        1. 7.3.10.1 Overtemperature-Shutdown Ideal-Diode Mode
    4. 7.4 Start-Up Sequence
    5. 7.5 Safe Operation Area (SOA)
      1. 7.5.1 Repetitive SOA
    6. 7.6 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Slew Rate Selection
          1. 8.2.2.1.1 Start-Up and Slew Rate With Bootstrap High-Side Supply
        2. 8.2.2.2 Signal Level-Shifting
        3. 8.2.2.3 Buck-Boost Converter Design
      3. 8.2.3 Application Curves
    3. 8.3 Do's and Don'ts
    4. 8.4 Power Supply Recommendations
      1. 8.4.1 Using an Isolated Power Supply
      2. 8.4.2 Using a Bootstrap Diode
        1. 8.4.2.1 Diode Selection
        2. 8.4.2.2 Managing the Bootstrap Voltage
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Solder-Joint Reliability
        2. 8.5.1.2 Power-Loop Inductance
        3. 8.5.1.3 Signal-Ground Connection
        4. 8.5.1.4 Bypass Capacitors
        5. 8.5.1.5 Switch-Node Capacitance
        6. 8.5.1.6 Signal Integrity
        7. 8.5.1.7 High-Voltage Spacing
        8. 8.5.1.8 Thermal Recommendations
      2. 8.5.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Export Control Notice
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

8.2.2.1 Slew Rate Selection

The slew rate of LMG3522R030-Q1 can be adjusted between approximately 20 V/ns and 150 V/ns by connecting a resistor, RRDRV, from the RDRV pin to GND. The RDRV pin is a high-impedance node if a large RRDRV resistor is used. Therefore it can be susceptible to coupling from the drain or other fast-slewing high-voltage nodes if it is not well-shielded. This will manifest itself as an unstable switching dv/dt and in extreme cases transient faults due to the RDRV being detected as open. Shielding the pin in the layout should be a priority, however if this coupling is still a problem, a cap of up to 1 nF from RDRV to GND can be added to stabilize the pin voltage.

The slew rate affects GaN device performance in terms of:

  • Switching loss
  • Voltage overshoot
  • Noise coupling
  • EMI emission

Generally, high slew rates provide low switching loss, but high slew rates can also create higher voltage overshoot, noise coupling, and EMI emissions. Following the design recommendations in this data sheet helps mitigate the challenges caused by a high slew rate. The LMG3522R030-Q1 offers circuit designers the flexibility to select the proper slew rate for the best performance of their applications.