SNVSCR4D July   2024  – June 2026 TLA431 , TLA432

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  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 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Temperature Coefficient
    2. 7.2 Dynamic Impedance
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
      1. 8.4.1 Closed Loop
        1. 8.4.1.1 Stability (Closed Loop)
      2. 8.4.2 Open Loop (Comparator)
  10. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Shunt Regulator/Reference
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Programming Output/Cathode Voltage
          2. 9.2.1.2.2 Total Accuracy
          3. 9.2.1.2.3 Start-Up Time
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Comparator With Integrated Reference
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Basic Operation
            1. 9.2.2.2.1.1 Overdrive
          2. 9.2.2.2.2 Output Voltage and Logic Input Level
            1. 9.2.2.2.2.1 Input Resistance
        3. 9.2.2.3 Application Curve
    3. 9.3 System Examples
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Nomenclature
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information
9.2.2.2.2 Output Voltage and Logic Input Level

To use the TLA431 as a comparator, verify that the logic output is readable by the receiving logic device. This is accomplished by knowing the input high and low-level threshold voltage levels, typically denoted by VIH and VIL.

As seen in Figure 9-4, the output low-level voltage in open-loop/comparator mode is approximately 2V, which is typically sufficient for 5V supplied logic. However, 5V does not work for 3.3V and 1.8V supplied logic. To accommodate this, tie a resistive divider to the output to attenuate the output voltage to a voltage legible to the receiving low voltage logic device.

The output high voltage of TLA431 output high voltage is equal to VSUP due to TLA431 being open-collector. If VSUP is much higher than the receiving maximum input voltage tolerance of logic, attenuate the output to accommodate the outgoing reliability of logic.

When using a resistive divider on the output, be sure to make the sum of the resistive divider (R1 and R2 in Figure 9-3) is much greater than RSUP to not interfere with the ability of TLA431 to pull close to VSUP when turning off.