SBOS600D May   2014  – July 2018 REF2025 , REF2030 , REF2033 , REF2041

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Application Example
      2.      VREF and VBIAS vs Temperature
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  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
    6. 7.6 Typical Characteristics
  8. Parameter Measurement Information
    1. 8.1 Solder Heat Shift
    2. 8.2 Thermal Hysteresis
    3. 8.3 Noise Performance
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 VREF and VBIAS Tracking
      2. 9.3.2 Low Temperature Drift
      3. 9.3.3 Load Current
    4. 9.4 Device Functional Modes
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Low-Side, Current-Sensing Application
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Shunt Resistor
          2. 10.2.1.2.2 Differential Amplifier
          3. 10.2.1.2.3 Voltage Reference
          4. 10.2.1.2.4 Results
        3. 10.2.1.3 Application Curves
  11. 11Power-Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Related Links
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Community Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Solder Heat Shift

The materials used in the manufacture of the REF20xx have differing coefficients of thermal expansion, resulting in stress on the device die when the part is heated. Mechanical and thermal stress on the device die can cause the output voltages to shift, degrading the initial accuracy specifications of the product. Reflow soldering is a common cause of this error.

In order to illustrate this effect, a total of 92 devices were soldered on four printed circuit boards [23 devices on each printed circuit board (PCB)] using lead-free solder paste and the paste manufacturer suggested reflow profile. The reflow profile is as shown in Figure 40. The printed circuit board is comprised of FR4 material. The board thickness is 1.57 mm and the area is 171.54 mm × 165.1 mm.

The reference and bias output voltages are measured before and after the reflow process; the typical shift is displayed in Figure 41 and Figure 42. Although all tested units exhibit very low shifts (< 0.01%), higher shifts are also possible depending on the size, thickness, and material of the printed circuit board. An important note is that the histograms display the typical shift for exposure to a single reflow profile. Exposure to multiple reflows, as is common on PCBs with surface-mount components on both sides, causes additional shifts in the output bias voltage. If the PCB is exposed to multiple reflows, the device should be soldered in the second pass to minimize its exposure to thermal stress.

REF2025 REF2030 REF2033 REF2041 C044_SBOS600.pngFigure 40. Reflow Profile
REF2025 REF2030 REF2033 REF2041 C041_SBOS600.pngFigure 41. Solder Heat Shift Distribution, VREF (%)
REF2025 REF2030 REF2033 REF2041 C040_SBOS600.pngFigure 42. Solder Heat Shift Distribution, VBIAS (%)