SNVSBB0A May   2019  – November 2019 ATL431LI-Q1 , ATL432LI-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Temperature Coefficient
    2. 8.2 Dynamic Impedance
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
      1. 9.4.1 Open Loop (Comparator)
      2. 9.4.2 Closed Loop
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Comparator With Integrated Reference
      2. 10.2.2 Design Requirements
      3. 10.2.3 Detailed Design Procedure
        1. 10.2.3.1 Basic Operation
          1. 10.2.3.1.1 Overdrive
        2. 10.2.3.2 Output Voltage and Logic Input Level
          1. 10.2.3.2.1 Input Resistance
      4. 10.2.4 Application Curves
      5. 10.2.5 Precision LED Lighting Current Sink Regulator
        1. 10.2.5.1 Design Requirements
        2. 10.2.5.2 Detailed Design Procedure
          1. 10.2.5.2.1 Basic Operation
            1. 10.2.5.2.1.1 Output Current Range and Accuracy
          2. 10.2.5.2.2 Power Consumption
      6. 10.2.6 Shunt Regulator/Reference
        1. 10.2.6.1 Design Requirements
        2. 10.2.6.2 Detailed Design Procedure
          1. 10.2.6.2.1 Programming Output/Cathode Voltage
          2. 10.2.6.2.2 Total Accuracy
          3. 10.2.6.2.3 Stability
          4. 10.2.6.2.4 Start-Up Time
        3. 10.2.6.3 Application Curves
      7. 10.2.7 Isolated Flyback with Optocoupler
        1. 10.2.7.1 Design Requirements
          1. 10.2.7.1.1 Detailed Design Procedure
            1. 10.2.7.1.1.1 ATL431LI-Q1 Biasing
            2. 10.2.7.1.1.2 Resistor Feedback Network
      8. 10.2.8 Adjustable Reference for Tracking LDO
        1. 10.2.8.1 Design Requirements
        2. 10.2.8.2 Detailed Design Procedure
          1. 10.2.8.2.1 External Capacitors
    3. 10.3 System Examples
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Device Nomenclature
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Related Links
    4. 13.4 Receiving Notification of Documentation Updates
    5. 13.5 Support Resources
    6. 13.6 Trademarks
    7. 13.7 Electrostatic Discharge Caution
    8. 13.8 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

10.2.3.1.1 Overdrive

Slow or inaccurate responses can also occur when the reference pin is not provided enough overdrive voltage. This is the amount of voltage that is higher than the internal virtual reference. The internal virtual reference voltage is within the range of 2.5 V ±(0.5% or 1.0%) depending on which version is being used. The more overdrive voltage provided, the faster the ATL431LI-Q1 will respond.

For applications where ATL431LI-Q1 is being used as a comparator, it is best to set the trip point to greater than the positive expected error (that is +1.0% for the A version). For fast response, setting the trip point to >10% of the internal VREF suffices.

For minimal voltage drop or difference from Vin to the ref pin, TI recommends to use an input resistor <10 kΩ to provide Iref.