SBAS901C July   2018  – October 2020 REF34-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1. 6.1 Pin Functions
  7. 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 Electrical Characteristics
  8. 8 Typical Characteristics
  9. 9 Parameter Measurement Information
    1. 9.1 Solder Heat Shift
    2. 9.2 Long-Term Stability
    3. 9.3 Thermal Hysteresis
    4. 9.4 Power Dissipation
    5. 9.5 Noise Performance
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1 Supply Voltage
      2. 10.3.2 Low Temperature Drift
      3. 10.3.3 Load Current
    4. 10.4 Device Functional Modes
      1. 10.4.1 EN Pin
  11. 11Application and Implementation
    1. 11.1 Application Information
    2. 11.2 Typical Applications
      1. 11.2.1 Basic Voltage Reference Connection
        1. 11.2.1.1 Design Requirements
        2. 11.2.1.2 Detailed Design Procedure
          1. 11.2.1.2.1 Input and Output Capacitors
          2. 11.2.1.2.2 4-Wire Kelvin Connections
          3. 11.2.1.2.3 VIN Slew Rate Considerations
          4. 11.2.1.2.4 Shutdown/Enable Feature
        3. 11.2.1.3 Application Curves
      2. 11.2.2 Advanced Driver Assistance Systems (ADAS) Microcontroller Connection
        1. 11.2.2.1 Basic Voltage Reference Connection
        2. 11.2.2.2 Design Requirements
        3. 11.2.2.3 Detailed Design Procedure
        4. 11.2.2.4 Enable Feature in ADAS
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Documentation Support
      1. 14.1.1 Related Documentation
    2. 14.2 Receiving Notification of Documentation Updates
    3. 14.3 Support Resources
    4. 14.4 Trademarks
    5. 14.5 Electrostatic Discharge Caution
    6. 14.6 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

9.3 Thermal Hysteresis

Thermal hysteresis is measured with the REF34-Q1 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. Hysteresis can be expressed by Equation 1:

Equation 1. GUID-3D4CA857-39BB-4446-A74A-EC85DD7ABA6A-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.

Typical thermal hysteresis distribution is as shown in Figure 9-6.

GUID-98196DCE-CE9C-4726-9CE9-CB4F47A0E85C-low.gifFigure 9-6 Thermal Hysteresis Distribution (VREF) - DBV Package (Cycle 1)
GUID-20201020-CA0I-BHWG-B2KD-JF2DZF9MTMMH-low.gifFigure 9-8 Thermal Hysteresis Distribution (VREF) - DGK Package (Cycle 1)
GUID-D8635073-378E-4EBC-B691-D72930666755-low.gifFigure 9-7 Thermal Hysteresis Distribution (VREF) - DBV Package (Cycle 2)
GUID-20201020-CA0I-2QF8-CCJF-XWSVGRNXCRPP-low.gifFigure 9-9 Thermal Hysteresis Distribution (VREF) - DGK Package (Cycle 2)