JAJSLK5B October   2020  – May 2022 LMG3422R050 , LMG3425R050

PRODUCTION DATA  

  1. 特長
  2. アプリケーション
  3. 概要
  4. Revision History
  5. Device Comparison
  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 Switching Characteristics
    7. 7.7 Typical Characteristics
  8. Parameter Measurement Information
    1. 8.1 Switching Parameters
      1. 8.1.1 Turn-On Times
      2. 8.1.2 Turn-Off Times
      3. 8.1.3 Drain-Source Turn-On Slew Rate
      4. 8.1.4 Turn-On and Turn-Off Switching Energy
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  GaN FET Operation Definitions
      2. 9.3.2  Direct-Drive GaN Architecture
      3. 9.3.3  Drain-Source Voltage Capability
      4. 9.3.4  Internal Buck-Boost DC-DC Converter
      5. 9.3.5  VDD Bias Supply
      6. 9.3.6  Auxiliary LDO
      7. 9.3.7  Fault Detection
        1. 9.3.7.1 Overcurrent Protection and Short-Circuit Protection
        2. 9.3.7.2 Overtemperature Shutdown
        3. 9.3.7.3 UVLO Protection
        4. 9.3.7.4 Fault Reporting
      8. 9.3.8  Drive Strength Adjustment
      9. 9.3.9  Temperature-Sensing Output
      10. 9.3.10 Ideal-Diode Mode Operation
    4. 9.4 Start Up Sequence
    5. 9.5 Safe Operation Area (SOA)
      1. 9.5.1 Safe Operation Area (SOA) - Repetitive SOA
    6. 9.6 Device Functional Modes
  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 Slew Rate Selection
          1. 10.2.2.1.1 Start-Up and Slew Rate With Bootstrap High-Side Supply
        2. 10.2.2.2 Signal Level-Shifting
        3. 10.2.2.3 Buck-Boost Converter Design
      3. 10.2.3 Application Curves
    3. 10.3 Do's and Don'ts
  11. 11Power Supply Recommendations
    1. 11.1 Using an Isolated Power Supply
    2. 11.2 Using a Bootstrap Diode
      1. 11.2.1 Diode Selection
      2. 11.2.2 Managing the Bootstrap Voltage
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Solder-Joint Reliability
      2. 12.1.2 Power-Loop Inductance
      3. 12.1.3 Signal-Ground Connection
      4. 12.1.4 Bypass Capacitors
      5. 12.1.5 Switch-Node Capacitance
      6. 12.1.6 Signal Integrity
      7. 12.1.7 High-Voltage Spacing
      8. 12.1.8 Thermal Recommendations
    2. 12.2 Layout Examples
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 サポート・リソース
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Export Control Notice
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ(パッケージ|ピン)
  • RQZ|54
サーマルパッド・メカニカル・データ
発注情報

Power-Loop Inductance

The power loop, comprising the two devices in the half bridge and the high-voltage bus capacitance, undergoes high di/dt during switching events. By minimizing the inductance of this loop, ringing and electro-magnetic interference (EMI) can be reduced, as well as reducing voltage stress on the devices.

Place the power devices as close as possible to minimize the power-loop inductance. The decoupling capacitors are positioned in line with the two devices. They can be placed close to either device. In Layout Examples, the decoupling capacitors are placed on the same layer as the devices. The return path (PGND in this case) is located on second layer in close proximity to the top layer. By using inner layer and not bottom layer, the vertical dimension of the loop is reduced, thus minimizing inductance. A large number of vias near both the device terminal and bus capacitance carries the high-frequency switching current to inner layer while minimizing impedance.

The power loop inductance can be estimated based on the ringing frequency fring of the drain-source voltage switching waveform based on the following equation

Equation 1. Lpl=14π2fring2Cring

where Cring is equal to COSS at the bus voltage (refer to Figure 7-8 for the typical value) plus the drain-source parasitic capacitance from the board and load inductor or transformer.

As the parasitic capacitance of load components is hard to character, it's recommended to capture the VDS switching waveform without load components to estimate the power loop inductance. Typically, the power loop inductance of the Layout Example is around 2.5 nH.