SBOS729B October   2015  – October 2025 DRV425

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Fluxgate Sensor Front-End
        1. 6.3.1.1 Fluxgate Sensor
        2. 6.3.1.2 Bandwidth
        3. 6.3.1.3 Differential Driver for the Internal Compensation Coil
        4. 6.3.1.4 Magnetic Field Range, Overrange Indicator, and Error Flag
      2. 6.3.2 Shunt-Sense Amplifier
      3. 6.3.3 Voltage Reference
      4. 6.3.4 Low-Power Operation
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Linear Position Sensing
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Curves
      2. 7.2.2 Current Sensing in Busbars
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Power Supply Decoupling
      2. 7.3.2 Power-On Start-Up and Brownout
      3. 7.3.3 Power Dissipation
        1. 7.3.3.1 Thermal Pad
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
      1. 8.1.1 Related Documentation
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Receiving Notification of Documentation Updates
    5. 8.5 Support Resources
    6. 8.6 Trademarks
    7. 8.7 Electrostatic Discharge Caution
    8. 8.8 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2.2.1 Design Requirements

To measure the field gradient in the busbar, two DRV425 sensors are placed inside the hole at a well-defined distance by mounting them on opposite sides of a PCB that is inserted in the hole.  The measurement range and resolution of this design depends on the following factors:

  • Busbar geometry: a wider busbar means a larger measurement range and lower resolution.
  • Size of the hole: a larger diameter means a larger measurement range and lower resolution.
  • Distance between the two DRV425 sensors: a smaller distance increases the measurement range and resolution.

Each of these factors can be optimized to create the desired measurement range for a particular application. Measurement ranges of ±250A to ±1500A are achievable with this approach. Larger currents are supported with large busbar structures and minimized distance between the two DRV425 sensors. Use the parameters listed in Table 7-2 as a starting point of the design.

Table 7-2 Design Parameters
DESIGN PARAMETEREXAMPLE VALUE
Current rangeUp to ±1500A
Supply voltage, VDD3.0V to 5.5V
Reference voltage, VREFINVDD / 2