SNOSD81B September   2018  – January 2020

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Simplified Block Diagram
      2.      Switching Performance at >100 V/ns
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. Parameter Measurement Information
    1. 7.1 Switching Parameters
      1. 7.1.1 Turn-on Delays
      2. 7.1.2 Turn-off Delays
      3. 7.1.3 Drain Slew Rate
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Direct-Drive GaN Architecture
      2. 8.3.2 Internal Buck-Boost DC-DC Converter
      3. 8.3.3 Internal Auxiliary LDO
      4. 8.3.4 Start Up Sequence
      5. 8.3.5 R-C Decoupling for IN pin
      6. 8.3.6 Low Power Mode
      7. 8.3.7 Fault Detection
        1. 8.3.7.1 Over-current Protection
        2. 8.3.7.2 Over-Temperature Protection and UVLO
      8. 8.3.8 Drive Strength Adjustment
    4. 8.4 Safe Operation Area (SOA)
      1. 8.4.1 Repetitive SOA
  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 Slew Rate Selection
          1. 9.2.2.1.1 Startup and Slew Rate with Bootstrap High-Side Supply
        2. 9.2.2.2 Signal Level-Shifting
        3. 9.2.2.3 Buck-Boost Converter Design
    3. 9.3 Do's and Don'ts
  10. 10Power Supply Recommendations
    1. 10.1 Using an Isolated Power Supply
    2. 10.2 Using a Bootstrap Diode
      1. 10.2.1 Diode Selection
      2. 10.2.2 Managing the Bootstrap Voltage
      3. 10.2.3 Reliable Bootstrap Start-up
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Power Loop Inductance
      2. 11.1.2 Signal Ground Connection
      3. 11.1.3 Bypass Capacitors
      4. 11.1.4 Switch-Node Capacitance
      5. 11.1.5 Signal Integrity
      6. 11.1.6 High-Voltage Spacing
      7. 11.1.7 Thermal Recommendations
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Bypass Capacitors

The gate drive loop impedance must also be minimized to yield strong performance. Although the gate driver is integrated on package, the bypass capacitance for the driver is placed externally on the PCB board. As the GaN device is turned off to a negative voltage, the impedance of the negative source is included in the crucial turn-off path. As the critical hold-off path passes through this external bypass capacitor attached to VNEG, this capacitor must be located close to the LMG341xR050. In the Figure 24, VNEG bypass capacitors C9 and C26 are located immediately adjacent to the pins on the IC with a direct connection to the SOURCE pin.

The bypass capacitors for the input supply (C8 and C23) and the 5V regulator (C5 and C7) must also be located immediately next to the IC with a close connection to the ground plane.