SNAS781G October   2020  – September 2023 REF70

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 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  REF7012 Electrical Characteristics
    6. 7.6  REF7025 Electrical Characteristics
    7. 7.7  REF7030 Electrical Characteristics
    8. 7.8  REF7033 Electrical Characteristics
    9. 7.9  REF7040 Electrical Characteristics
    10. 7.10 REF7050 Electrical Characteristics
    11. 7.11 Typical Characteristics
  9. 8 Parameter Measurement Information
    1. 8.1 Solder Heat Shift
    2. 8.2 Long-Term Stability
    3. 8.3 Thermal Hysteresis
    4. 8.4 Noise Performance
      1. 8.4.1 1/f Noise
      2. 8.4.2 Broadband Noise
    5. 8.5 Temperature Drift
    6. 8.6 Power Dissipation
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 EN Pin
    4. 9.4 Device Functional Modes
      1. 9.4.1 Basic Connections
      2. 9.4.2 Negative Reference Voltage
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Typical Application: Basic Voltage Reference Connection
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Input and Output Capacitors
            1. 10.2.1.2.1.1 Application Curve
          2. 10.2.1.2.2 Force and Sense Connection
      2. 10.2.2 Typical Application: DAC Force and Sense Reference Drive Circuit
        1. 10.2.2.1 Design Requirements
    3. 10.3 Power Supply Recommendation
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.3 Thermal Hysteresis

Thermal hysteresis is measured with the REF70 soldered to a PCB, similar to a real-world application. Thermal hysteresis for the device is defined as the change in output voltage after operating the device at 25°C, cycling the device through the specified temperature range, and returning to 25°C. This can be seen in Figure 8-6 to Figure 8-8. Hysteresis can be expressed by Equation 1:

Equation 1. GUID-D16E4841-5E47-4E44-A209-1F616C697FA6-low.gif

where

  • VHYST = thermal hysteresis (in units of ppm)
  • VNOM = the specified output voltage
  • VPRE = output voltage measured at 25°C pre-temperature cycling
  • VPOST = output voltage measured after the device has cycled from 25°C through the specified temperature range of –40°C to +125°C and returns to 25°C.
GUID-20201210-CA0I-XRZD-FLDF-9SQ4QQJ7TXGB-low.svgFigure 8-6 REF7025QFKHR Thermal Hysteresis Distribution (-40°C to 125°C)
GUID-20211207-SS0I-JBLB-TXLD-MZ5P3F2FRCG6-low.svgFigure 8-8 REF7012QFKHR Thermal Hysteresis Distribution (-40°C to 125°C)
GUID-20230313-SS0I-KGBS-HHJV-HW8RPDDTDQZP-low.svgFigure 8-7 REF7012QDGKR Thermal Hysteresis Distribution (-40°C to 125°C)