TIDUF88 October   2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Accuracy of Bus Voltage Measuring
      2. 2.2.2 Shunt Current Measuring
      3. 2.2.3 Insulation Impedance Monitor
    3. 2.3 Highlighted Products
      1. 2.3.1 BQ79731-Q1
      2. 2.3.2 TPSI2140-Q1
      3. 2.3.3 ISO7841
      4. 2.3.4 SN6507
      5. 2.3.5 TPS7B6950
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Test Setup
    3. 3.3 Test Results
      1. 3.3.1 Bus Voltage Accuracy
      2. 3.3.2 Current Sensing Accuracy
      3. 3.3.3 Insulation Impedance Accuracy
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author

2.3.3 ISO7841

The ISO7841x device is a high-performance, quad-channel digital isolator with a 8000VPK isolation voltage. This device has reinforced isolation certifications according to VDE, CSA, CQC, and TUV. The isolator provides high electromagnetic immunity and low-emissions at low-power consumption while isolating CMOS or LVCMOS digital inputs and outputs. Each isolation channel has a logic input and output buffer separated by a silicon-dioxide (SiO2) insulation barrier.

This device comes with enable pins that can be used to put the respective outputs in high-impedance for multi-controller driving applications and to reduce power consumption. The ISO7841 device has three forward and one reverse-direction channels. If the input power or signal is lost, the default output is high for the ISO7841 device and low for the ISO7841F device.

Used in conjunction with isolated power supplies, this device helps prevent noise currents on a data bus 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 ISO7841 device has been significantly enhanced to ease system-level ESD, EFT, surge, and emissions compliance.

The ISO7841 device is available in 16-pin SOIC wide-body (DW) and extra-wide body (DWW) packages.