SNOSD81B September   2018  – January 2020

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Block Diagram
      2.      Switching Performance at >100 V/ns
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. 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. 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. 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

10.2.1 Diode Selection

LMG341xR050 has no reverse-recovery charge and little output charge. Hard-switched circuits using LMG341xR050 also exhibit high voltage slew rates. A compatible bootstrap diode must exhibit low output charge, and if used in a hard-switching circuit, a very low reverse-recovery charge.

For soft-switching applications, the MCC UFM15PL ultra-fast silicon diode can be used. The output charge of 2.7 nC is small in comparison with the switching transistors, so it will have little influence on switching performance. In a hard-switching application, the reverse recovery charge of the silicon diode may contribute an additional loss to the circuit.

For hard-switched applications, a silicon carbide diode can be used to avoid reverse-recovery effects. The Cree C3D1P7060Q SiC diode has an output charge of 4.5 nC and a reverse recovery charge of about 5 nC. There will be some losses using this diode due to the output charge, but these will not dominate the switching stage’s losses.