SBOS600F July   2018  – July 2026 REF20

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 Long-Term Stability
    3. 7.3 Thermal Hysteresis
    4. 7.4 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 Low-Side, Current-Sensing Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Shunt Resistor
          2. 9.2.1.2.2 Differential Amplifier
          3. 9.2.1.2.3 Voltage Reference
          4. 9.2.1.2.4 Results
        3. 9.2.1.3 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
9.2.1.2.1 Shunt Resistor

Figure 9-2 shows the value of VSHUNT as the ground potential for the system load. If the value of VSHUNT is too large, issues can arise when interfacing with systems with a ground potential of 0V. A value of VSHUNT that is too negative can violate the input common-mode voltage of the differential amplifier in addition to potential interfacing issues. Therefore, limiting the voltage across the shunt resistor is important. Use Equation 7 to calculate the maximum value of RSHUNT.

Equation 7. R S H U N T m a x = V S H U N T m a x I L O A D m a x

Given that the maximum shunt voltage is ±25mV and the load current range is ±2.5A, use Equation 8 to calculate the maximum shunt resistance.

Equation 8. R S H U N T m a x = V S H U N T m a x I L O A D m a x = 25 m V 2.5 A = 10 m Ω

To minimize errors over temperature, select a low-drift shunt resistor. To minimize offset error, select a shunt resistor with the lowest tolerance. For this design, the Y14870R01000B9W resistor is used.