SLLA529 October   2020 ISO7741

 

  1. 1 Introduction
  2. 2 General Considerations
  3. 3 Group-Isolated Analog Input Modules
    1.     Requirements for Digital Isolator in Group-Isolated AI modules:
    2.     Requirements for Isolated Power in Group-Isolated AI modules:
  4. 4 Channel-to-Channel Isolated Analog Input Modules
    1.     Requirements for Digital Isolator in channel-to-channel isolated AI modules
    2.     Requirements for Isolated Power in channel-to-channel isolated AI modules
  5. 5Isolation Products for Analog Input Modules
  6. 6Conclusion
  7. 7References
    1.     Trademarks

Requirements for Isolated Power in channel-to-channel isolated AI modules

The considerations for isolated power are similar as for group isolated modules. The isolated power supplies operate with very low currents (in the range of 10 mA), so efficiency at light loads is important. In some designs, the 24-V field supply needed for the analog sensors is provided by the analog input module itself, in which case the isolated power supply must also generate 24 V.