SBAS945A February   2022  – July 2022 AMC23C14

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 Diagrams
    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 Reference Input
      3. 7.3.3 Isolation Channel Signal Transmission
      4. 7.3.4 Open-Drain Digital Outputs
      5. 7.3.5 Power-Up and Power-Down Behavior
      6. 7.3.6 VDD1 Brownout and Power-Loss Behavior
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Overcurrent and Short-Circuit Current Detection
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
      2. 8.2.2 Overvoltage and Undervoltage Detection
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.2 Overvoltage and Undervoltage Detection

Industrial I/O modules are frequently powered by external field supplies with a nominal voltage of 24 V and a tolerance of –15% to +20%. In safety-critical applications, the controller-side may need to know whether the voltage is in the valid range for correct operation or not. Figure 8-2 shows the AMC23C14 in an application that monitors a 24-V supply on the high-side and signals undervoltage and overvoltage conditions to the programmable logic controller (PLC) on the low-side.

The voltage divider R5 and R6 is sized to trip the fixed internal 300-mV threshold when the power supply exceeds the minimum valid operating voltage of 20.4 V (24 V – 15%). In a second step, R1 (connected to the REF pin) is sized to trip the adjustable-threshold comparator when the power supply exceeds 28.8 V (24 V + 20%). The AMC23C14 is powered from the field supply and is protected against voltages greater than 30 V by a Zener diode (Z1) and shunt resistor R4.

When the power supply is below 20.4 V, both outputs of the AMC23C14 are in a Hi-Z state. Between 20.4 V and 28.8 V, OUT1 is in a Hi-Z state and OUT2 is actively pulled low. Both outputs are pulled low, as shown in Figure 8-3, when the power supply is above 28.8 V.

Figure 8-2 Using the AMC23C14 for Overvoltage and Undervoltage Detection
Figure 8-3 Output of the AMC23C14 in Supply Voltage Supervisor Application