SLLSEP4J March   2016  – October 2024 ISO7740 , ISO7741 , ISO7742

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  Power Ratings
    6. 5.6  Insulation Specifications
    7. 5.7  Safety-Related Certifications
    8. 5.8  Safety Limiting Values
    9. 5.9  Electrical Characteristics—5-V Supply
    10. 5.10 Supply Current Characteristics—5-V Supply
    11. 5.11 Electrical Characteristics—3.3-V Supply
    12. 5.12 Supply Current Characteristics—3.3-V Supply
    13. 5.13 Electrical Characteristics—2.5-V Supply 
    14. 5.14 Supply Current Characteristics—2.5-V Supply
    15. 5.15 Switching Characteristics—5-V Supply
    16. 5.16 Switching Characteristics—3.3-V Supply
    17. 5.17 Switching Characteristics—2.5-V Supply
    18. 5.18 Insulation Characteristics Curves
    19. 5.19 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Electromagnetic Compatibility (EMC) Considerations
    4. 7.4 Device Functional Modes
      1. 7.4.1 Device I/O Schematics
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
        1. 8.2.3.1 Insulation Lifetime
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 PCB Material
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

3 Description

The ISO774x devices are high-performance, quad-channel digital isolators with 5000VRMS (DW package) and 3000VRMS (DBQ package) isolation ratings per UL 1577. This family includes devices with reinforced insulation ratings according to VDE, CSA, TUV and CQC. The ISO7741B device is designed for applications that require basic insulation ratings only.

The ISO774x devices provide high electromagnetic immunity and low emissions at low power consumption, while isolating CMOS or LVCMOS digital I/Os. Each isolation channel has a logic input and output buffer separated by a double capacitive silicon dioxide (SiO2) insulation barrier. These devices come with enable pins which can be used to put the respective outputs in high impedance for multi-controller driving applications and to reduce power consumption. The ISO7740 device has all four channels in the same direction, the ISO7741 device has three forward and one reverse-direction channels, and theISO7742device has two forward and two reverse-direction channels. If the input power or signal is lost, default output is high for devices without suffix F and low for devices with suffix F. See the Device Functional Modes section for further details.

Used in conjunction with isolated power supplies, these devices help prevent noise currents on data buses, such as RS-485, RS-232, and CAN, or other circuits from entering the local ground and interfering with or damaging sensitive circuitry. Through remarkable chip design and layout techniques, electromagnetic compatibility of the ISO774x devices significantly enhanced to ease system-level ESD, EFT, surge, and emissions compliance. The ISO774x devices are available in 16-pin SOIC and QSOP packages.

ISO7740 ISO7741 ISO7742 Simplified Schematic

VCCI=Input supply, VCCO=Output supply

GNDI=Input ground, GNDO=Output ground

Simplified Schematic