SBASAQ4A june   2023  – august 2023 AMC3311-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 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
  8. 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 Isolation Channel Signal Transmission
      3. 7.3.3 Analog Output
      4. 7.3.4 Isolated DC/DC Converter
      5. 7.3.5 Diagnostic Output and Fail-Safe Behavior
    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 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input Filter Design
        2. 8.2.2.2 Differential to Single-Ended Output Conversion
      3. 8.2.3 Application Curve
    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
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

8.2 Typical Application

Figure 8-1 shows a simplified schematic of a traction inverter. The AMC3311-Q1 measures the DC bus voltage and an AMC23C12-Q1 isolated comparator is used for fast overvoltage detection. The DC bus voltage is divided down to an approximate 2-V level across the bottom two sense resistors (RSNS1 and RSNS2) of a high-impedance resistive divider. This voltage is sensed by the AMC3311-Q1. The AMC3311-Q1 digitizes the analog input signal on the high-side, transfers the data across the isolation barrier to the low-side, and reconstructs an analog signal that is presented as a differential voltage on the output pins OUTN and OUTP.

GUID-20230119-SS0I-N66X-DGJJ-HHWGRMCPJZHV-low.svg Figure 8-1 The AMC3311-Q1 in a Traction Inverter Application

The AMC3311-Q1 integrates an isolated power supply for the high-voltage side and therefore is particularly easy to use in applications that do not have a high-side supply readily available. In this example, the integrated power supply of the AMC3311-Q1 is also used to power the AMC23C12-Q1 isolated, high-speed comparator that is used for low-latency overvoltage detection on the DC bus.

The AMC23C12 isolated comparator senses the voltage across the bottom resistor (RSNS2) of the resistive divider and compares that value against an adjustable reference voltage (VREF). The isolated comparator pulls down the open-drain output on the low-side whenever the input voltage exceeds the reference value. For a detailed description of the isolated comparator, see the AMC23C12-Q1 data sheet available for download at ti.com.

The bottom resistor in the resistive divider is split into two equal-value resistors (RSNS1 and RSNS2) to accommodate the headroom requirements of the reference voltage (VREF) of the isolated comparator, as explained in the Detailed Design Procedure section.