ZHCSLW2C September   2021  – April 2022 ISOW7740 , ISOW7741 , ISOW7742 , ISOW7743 , ISOW7744

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  5. 说明(接续)
  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  Power Ratings
    6. 7.6  Insulation Specifications
    7. 7.7  Safety-Related Certifications
    8. 7.8  Safety Limiting Values
    9. 7.9  Electrical Characteristics - Power Converter
    10. 7.10 Supply Current Characteristics - Power Converter
    11. 7.11 Electrical Characteristics Channel Isolator - VIO, VISOIN = 5-V
    12. 7.12 Supply Current Characteristics Channel Isolator - VIO, VISOIN = 5-V
    13. 7.13 Electrical Characteristics Channel Isolator - VIO, VISOIN = 3.3-V
    14. 7.14 Supply Current Characteristics Channel Isolator - VIO, VISOIN = 3.3-V
    15. 7.15 Electrical Characteristics Channel Isolator - VIO, VISOIN = 2.5-V
    16. 7.16 Supply Current Characteristics Channel Isolator - VIO, VISOIN = 2.5-V
    17. 7.17 Electrical Characteristics Channel Isolator - VIO, VISOIN = 1.8-V
    18. 7.18 Supply Current Characteristics Channel Isolator - VIO, VISOIN = 1.8-V
    19. 7.19 Switching Characteristics - 5-V Supply
    20. 7.20 Switching Characteristics - 3.3-V Supply
    21. 7.21 Switching Characteristics - 2.5-V Supply
    22. 7.22 Switching Characteristics - 1.8-V Supply
    23. 7.23 Insulation Characteristics Curves
    24. 7.24 Typical Characteristics
  8. Parameter Measurement Information
  9. Detailed Description
    1. 9.1 Overview
      1. 9.1.1 Power Isolation
      2. 9.1.2 Signal Isolation
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Electromagnetic Compatibility (EMC) Considerations
      2. 9.3.2 Power-Up and Power-Down Behavior
      3. 9.3.3 Protection Features
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device I/O Schematics
  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
      3. 10.2.3 Application Curve
      4. 10.2.4 Insulation Lifetime
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 PCB Material
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Development Support
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 支持资源
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 术语表
  14. 14Mechanical, Packaging, and Orderable Information

Power Isolation

The integrated isolated DC-DC converter uses advanced circuit and on-chip layout techniques to reduce radiated emissions and achieve upto 46% typical efficiency. The integrated transformer uses thin film polymer as the insulation barrier. Output voltage of power converter can be controlled to 3.3 V or 5 V using VSEL pin. The DC-DC converter can be switched off using the EN/FLT pin to save power. The output voltage, VISOOUT , is monitored and feedback information is conveyed to the primary side through a dedicated isolation channel. VISOOUT needs to be connected to VISOIN to ensure the feedback channel is properly powered to regulate the DC-DC converter. This can be achieved by connecting the pins directly or through an LDO that remains powered up at all times. A ferrite bead is recommended between Visoout and Visoin to further reduce emissions. See the Section 10.2 section. The duty cycle of the primary switching stage is adjusted accordingly. The fast feedback control loop of the power converter ensures low overshoots and undershoots during load transients. Undervoltage lockout (UVLO) with hysteresis is integrated on the VIO, VDD and VISOIN supplies which ensures robust fails-safe system performance under noisy conditions. An integrated soft-start mechanism ensures controlled inrush current and avoids any overshoot on the output during power up.