SBOS697B September   2014  – July 2026 REF19

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 Solder Heat Shift
    2. 7.2 Thermal Hysteresis
    3. 7.3 Noise Performance
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 VREF and VBIAS Tracking
      2. 8.3.2 Low Temperature Drift
      3. 8.3.3 Load Current
    4. 8.4 Device Functional Modes
  10. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Shunt Resistor
        2. 9.2.2.2 Differential Amplifier
        3. 9.2.2.3 Voltage Reference
        4. 9.2.2.4 Results
      3. 9.2.3 Application Curves
    3. 9.3 Power-Supply Recommendations
    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

7.2 Thermal Hysteresis

The measurement of thermal hysteresis occurs with the REF19xx soldered to a PCB, similar to a real-world application. The definitions of thermal hysteresis for the device is 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. Express hysteresis using Equation 1:

Equation 1. V H Y S T = ( | V P R E - V P O S T | V N O M ) × 10 6 ( p p m )

where

  • VHYST = thermal hysteresis (in units of ppm),
  • VNOM = the specified output voltage,
  • VPRE = output voltage measured at 25°C pre-temperature cycling, and
  • VPOST = output voltage measured after the device has cycled from 25°C through the specified temperature range from –40°C to 125°C and returns to 25°C.

Typical thermal hysteresis distribution is as shown in Figure 7-4 and Figure 7-5.

REF19 Thermal Hysteresis Distribution (VREF)Figure 7-4 Thermal Hysteresis Distribution (VREF)
REF19 Thermal Hysteresis Distribution (VBIAS)Figure 7-5 Thermal Hysteresis Distribution (VBIAS)