SBASA84A February   2021  – July 2021 AMC3302-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Related Certifications
    8. 6.8  Safety Limiting Values
    9. 6.9  Electrical Characteristics
    10. 6.10 Switching Characteristics
    11. 6.11 Timing Diagram
    12. 6.12 Insulation Characteristics Curves
    13. 6.13 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Analog Input
      2. 7.3.2 Data Isolation Channel Signal Transmission
      3. 7.3.3 Analog Output
      4. 7.3.4 Isolated DC/DC Converter
      5. 7.3.5 Diagnostic Output
    4. 7.4 Device Functional Modes
  8. 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
        1. 8.2.2.1 Shunt Resistor Sizing
        2. 8.2.2.2 Input Filter Design
        3. 8.2.2.3 Differential to Single-Ended Output Conversion
      3. 8.2.3 Application Curve
    3. 8.3 What to Do and What Not to Do
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.5 Diagnostic Output

As shown in Figure 7-3, the open-drain DIAG pin can be monitored to confirm the device is operational and the output voltage is valid. During power-up, the DIAG pin is actively held low until the high-side supply is in regulation and the device operates properly. During normal operation, the DIAG pin is in high-impedance (Hi-Z) state and is pulled high through an external pullup resistor. The DIAG pin is actively pulled low if:

  • The low-side does not receive data from the high-side (for example, because of a loss of power on the high side). In this case, the amplifier outputs are driven to the VFAILSAFE value, see Figure 7-2.
  • The high-side DC/DC output voltage (DCDC_OUT) or the high-side LDO output voltage (HLDO_OUT) drop below their respective undervoltage detection thresholds (brown-out). In this case, the low-side may still receive data from the high-side but the data may not be valid. The amplifier outputs are driven to VFAILSAFE value, see Figure 7-2.
GUID-20201216-CA0I-CQ47-SNML-3HC8LGPW7V2M-low.gif Figure 7-3 DIAG Output Under Different Operating Conditions

During normal operation, the DIAG pin is in a high-impedance state. Connect the DIAG pin to a pullup resistor or leave open if not used.