SNOSDL4 June   2025 LMG2656

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 GaN Power FET Switching Parameters
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  GaN Power FET Switching Capability
      2. 7.3.2  Turn-On Slew-Rate Control
      3. 7.3.3  Current-Sense Emulation
      4. 7.3.4  Bootstrap Diode Function
      5. 7.3.5  Input Control Pins (EN, INL, INH, GDH)
      6. 7.3.6  INL - INH Interlock
      7. 7.3.7  AUX Supply Pin
        1. 7.3.7.1 AUX Power-On Reset
        2. 7.3.7.2 AUX Under-Voltage Lockout (UVLO)
      8. 7.3.8  BST Supply Pin
        1. 7.3.8.1 BST Power-On Reset
        2. 7.3.8.2 BST Under-Voltage Lockout (UVLO)
      9. 7.3.9  Overcurrent Protection
      10. 7.3.10 Overtemperature Protection
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 LLC Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 AHB Application
      3. 8.2.3 Motor Drives Application
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Solder-Joint Stress Relief
        2. 8.4.1.2 Signal-Ground Connection
        3. 8.4.1.3 CS Pin Signal
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

6.1 GaN Power FET Switching Parameters

Figure 6-1 shows the circuit used to measure the GaN power FET switching parameters. The circuit is operated as a double-pulse tester. Consult external references for double-pulse tester details. The circuit is placed in the boost configuration to measure the low-side GaN switching parameters. The circuit is placed in the buck configuration to measure the high-side GaN switching parameters. The GaN FET not being measured in each configuration (high-side in the boost and low-side in the buck) acts as the double-pulse tester diode and circulates the inductor current in the off-state, third-quadrant conduction mode. Table 6-1 shows the details for each configuration.


LMG2656 GaN Power FET Switching Parameters Test Circuit

Figure 6-1 GaN Power FET Switching Parameters Test Circuit
Table 6-1 GaN Power FET Switching Parameters Test Circuit Configuration Details
CONFIGURATION GaN FET UNDER TEST GaN FET ACTING AS DIODE SBOOST SBUCK VINL VINH VGDH
Boost Low-side High-side Closed Open Double-pulse waveform 0V 0V
Buck High-side Low-side Open Closed 0V Double-pulse waveform 0V
Buck High-side Low-side Open Closed 0V 0V Double-pulse waveform

Figure 6-2 shows the GaN power FET switching parameters.

The GaN power FET turn-on transition has three timing components: drain-current turn-on delay time td(on)(Idrain), turn-on delay time td(on), and turn-on rise time tr(on). Note that the turn-on rise time is the same as the VDS 80% to 20% fall time. All three turn-on timing components are a function of the RDRVx pin setting.

The GaN power FET turn-off transition has two timing components: turn-off delay time td(off), and turn-off fall time tf(off). Note that the turn-off fall time is the same as the VDS 20% to 80% rise time. The turn-off timing components are independent of the RDRVx pin setting, but heavily dependent on the LHB current.

The turn-on slew rate is measured over a turn-on rise time voltage delta (240V) to obtain a slew rate which is useful for EMI design. The RDRVx pin is used to program the slew rate.


LMG2656 GaN Power FET Switching Parameters

Figure 6-2 GaN Power FET Switching Parameters