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

8.2.1.2.5 Surge, ESD, and EFT Tests

Digital input modules are subject to surge (IEC 61000-4-5), electrostatic discharge or ESD (IEC 61000-4-2) and electrical fast transient or EFT (IEC 61000-4-4) tests. The surge impulse waveform has the highest energy and the widest pulse width, and is therefore the most stringent test of the three.

Figure 8-2 shows the application diagram for Type 1 and 3 systems. For a 1-kVPP surge test between the input terminals and protection earth (PE), a value of 1kΩ for RTHR and 10nF for CIN is recommended. Table 8-1 lists a summary of recommended component values to meet different levels of EMC requirements for Type 1 and 3 systems.

Table 8-1 Surge, IEC ESD and EFT
IEC 61131-2 TYPERSENSERTHCINSURGEIEC ESDIEC EFT
LINE-TO-PELINE-TO-LINELINE-TO-FGND
Type 15622.5kΩ10nF±1 kV±1 kV±1 kV±6 kV±4 kV
Type 35621kΩ10nF±1 kV±1 kV±500V±6 kV±4 kV
330nF±1 kV±1 kV±1 kV±6 kV±4 kV

Figure 8-9 shows the test setup and application circuit used for surge testing. A noise filtering capacitor of 500pF is recommended between the FGND pin and PE (earth). The total value of effective capacitance between the FGND pin and any other ground potential (including PE) must not exceed 500pF for optimum surge performance. For line-to-PE test (common-mode test), the FGND pin is connected to the auxiliary equipment (AE) through a decoupling network.

ISO1211 ISO1212 Setup and Application Circuit Used for Surge Test
A. For line-to-PE test, FGND is connected to the auxiliary equipment (AE) through a decoupling network.
B. A noise filtering capacitor of about 500pF is recommended between the FGND pin and PE (earth). The total value of effective capacitance between the FGND pin and any other ground potential (including PE) must not exceed 500pF for optimum performance.
Figure 8-9 Setup and Application Circuit Used for Surge Test

For higher voltage levels of surge tests or for faster systems that can not use a large value for CIN, TVS diodes or varistors can be used to meet EMC requirements. Type 2 systems that use a smaller value for RTHR can also require TVS diodes or varistors for surge protection. Figure 8-10 shows an example usage of TVS diodes for surge protection. The recommended components for surge protection are VCAN26A2-03S (TVS, Vishay), EZJ-P0V420WM (Varistor, Panasonic), and GSOT36C (TVS, Vishay).

Use of the RTHR resistor also reduces the peak current requirement for the TVS diodes, making them smaller and cost effective. For example, a 2-kV surge through a 1kΩ RTHR resistor creates only 2A peak current. Also, because of voltage drop across the RTHR resistor in normal operation, the working voltage requirement for the varistor or TVS diodes is reduced. For example, for a RTHR value of 1kΩ and an RSENSE value of 562Ω, a module designed for 30V inputs only requires 28V TVS diodes because the RTHR resistor drops more than 2V.

ISO1211 ISO1212 TVS Diodes Used Instead of a Filtering Capacitor for Surge Protection in Faster SystemsFigure 8-10 TVS Diodes Used Instead of a Filtering Capacitor for Surge Protection in Faster Systems