SLLSEY7G June   2017  – February 2025 ISO1211 , ISO1212

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—DC Specification
    10. 5.10 Switching Characteristics—AC Specification
    11. 5.11 Insulation Characteristics Curves
    12. 5.12 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Test Circuits
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
    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 Sinking Inputs
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Setting Current Limit and Voltage Thresholds
          2. 8.2.1.2.2 Thermal Considerations
          3. 8.2.1.2.3 Designing for 48V Systems
          4. 8.2.1.2.4 Designing for Input Voltages Greater Than 60V
          5. 8.2.1.2.5 Surge, ESD, and EFT Tests
          6. 8.2.1.2.6 Multiplexing the Interface to the Host Controller
          7. 8.2.1.2.7 Status LEDs
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Sourcing Inputs
      3. 8.2.3 Sourcing and Sinking Inputs (Bidirectional Inputs)
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Related Links
    4. 9.4 Receiving Notification of Documentation Updates
    5. 9.5 Support Resources
    6. 9.6 Trademarks
    7. 9.7 Electrostatic Discharge Caution
    8. 9.8 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

8.2.1.2.6 Multiplexing the Interface to the Host Controller

The ISO121x devices provide an output-enable pin on the controller side (EN). Setting the EN pin to 0 causes the output buffers to be in the high-impedance state. This feature can be used to multiplex the outputs of multiple ISO121x devices on the same host-controller input, reducing the number of pins on the host controller.

In the example shown in Figure 8-11, two sets of 8-channel inputs are multiplexed, reducing the number of input pins required on the controller from 16 to 10. Similarly, if four sets of 8-channel inputs are multiplexed, the number of pins on the controller is reduced from 32 to 12.

ISO1211 ISO1212 Using the Output Enable Option to Multiplex the Interface to the Host ControllerFigure 8-11 Using the Output Enable Option to Multiplex the Interface to the Host Controller