SNAS856A September   2024  – March 2025 REF80

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 Thermal Information
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Electrical Characteristics
    6. 6.6 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 Heater
      2. 7.3.2 Buried Zener Reference
  9. 8 Parameter Measurement Information
    1. 8.1 Long-Term Stability
    2. 8.2 Temperature Drift
    3. 8.3 Thermal Hysteresis
    4. 8.4 Noise Performance
      1. 8.4.1 1/f Noise
      2. 8.4.2 Broadband Noise
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical Application: Basic Voltage Reference Connection
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Typical Application Circuits
        1. 9.2.2.1 Precision Voltage Divider Connection
        2. 9.2.2.2 Calibration Signal
    3. 9.3 Power Supply Recommendation
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.3 Thermal Hysteresis

Thermal hysteresis is measured with the REF80 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 0°C to 70°C temperature range, and returning to 25°C. Thermal hysteresis for REF80 reduces significantly from second cycle ownwards as shown in Figure 8-4 and Figure 8-5. Hysteresis can be expressed by Equation 3

Equation 3. V H Y S T ( p p m )   =   ( | V P R E - V P O S T | V P R E ) × 10 6

where-

  • VHYST = thermal hysteresis (in units of ppm)
  • 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 0°C to75°C and returns to 25°C.
REF80 Thermal Hysteresis (Cycle 1) Distribution (0°C to 70°C)Figure 8-4 Thermal Hysteresis (Cycle 1) Distribution (0°C to 70°C)
REF80 Thermal Hysteresis (Cycle 2) Distribution (0°C to 70°C)Figure 8-5 Thermal Hysteresis (Cycle 2) Distribution (0°C to 70°C)