SLVS139X July   1996  – May 2018 TLV431 , TLV431A , TLV431B

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Simplified Schematic
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 for TLV431
    6. 6.6 Electrical Characteristics for TLV431A
    7. 6.7 Electrical Characteristics for TLV431B
    8. 6.8 Typical Characteristics
  7. Parameter Measurement Information
  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 Open Loop (Comparator)
      2. 8.4.2 Closed Loop
  9. Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Comparator With Integrated Reference (Open Loop)
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Basic Operation
          2. 9.2.1.2.2 Overdrive
          3. 9.2.1.2.3 Output Voltage and Logic Input Level
            1. 9.2.1.2.3.1 Input Resistance
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Shunt Regulator/Reference
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Programming Output/Cathode Voltage
          2. 9.2.2.2.2 Total Accuracy
          3. 9.2.2.2.3 Stability
        3. 9.2.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Related Links
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
  • DBZ|3
  • DBV|5
  • PK|3
  • LP|3
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Output Voltage and Logic Input Level

In order for TLV431 to properly be used as a comparator, the logic output must be 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 27, TLV431's output low level voltage in open-loop/comparator mode is approximately 1 V, which is sufficient for some 3.3-V supplied logic. However, this would not work for 2.5-V or 1.8-V supplied logic. To accommodate this a resistive divider can be tied to the output to attenuate the output voltage to a voltage legible to the receiving low voltage logic device.

TLV431's output high voltage is approximately Vsup due to TLV431 being open-collector. If Vsup is much higher than the receiving logic's maximum input voltage tolerance, the output must be attenuated to accommodate the outgoing logic's reliability.

When using a resistive divider on the output, be sure to make the sum of the resistive divider (R1 and R2 in Figure 26) is much greater than Rsup in order to not interfere with TLV431's ability to pull close to Vsup when turning off.