SLYS035A September   2022  – September 2023 TMAG5173-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  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  Temperature Sensor
    7. 6.7  Magnetic Characteristics For A1, B1, C1, D1
    8. 6.8  Magnetic Characteristics For A2, B2, C2, D2
    9. 6.9  Magnetic Temp Compensation Characteristics
    10. 6.10 I2C Interface Timing
    11. 6.11 Power up Timing
    12. 6.12 Timing Diagram
    13. 6.13 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Magnetic Flux Direction
      2. 7.3.2 Sensor Location
      3. 7.3.3 Interrupt Function
      4. 7.3.4 Device I2C Address
      5. 7.3.5 Magnetic Range Selection
      6. 7.3.6 Update Rate Settings
    4. 7.4 Device Functional Modes
      1. 7.4.1 Standby (Trigger) Mode
      2. 7.4.2 Sleep Mode
      3. 7.4.3 Continuous Measure Mode
    5. 7.5 Programming
      1. 7.5.1 I2C Interface
        1. 7.5.1.1 SCL
        2. 7.5.1.2 SDA
        3. 7.5.1.3 I2C Read/Write
          1. 7.5.1.3.1 Standard I2C Write
          2. 7.5.1.3.2 General Call Write
          3. 7.5.1.3.3 Standard 3-Byte I2C Read
          4. 7.5.1.3.4 1-Byte I2C Read Command for 16-Bit Data
          5. 7.5.1.3.5 1-Byte I2C Read Command for 8-Bit Data
          6. 7.5.1.3.6 I2C Read CRC
      2. 7.5.2 Data Definition
        1. 7.5.2.1 Magnetic Sensor Data
        2. 7.5.2.2 Temperature Sensor Data
        3. 7.5.2.3 Angle and Magnitude Data Definition
        4. 7.5.2.4 Magnetic Sensor Offset Correction
    6. 7.6 TMAG5173-Q1 Registers
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Select the Sensitivity Option
      2. 8.1.2 Temperature Compensation for Magnets
      3. 8.1.3 Sensor Conversion
        1. 8.1.3.1 Continuous Conversion
        2. 8.1.3.2 Trigger Conversion
        3. 8.1.3.3 Pseudo-Simultaneous Sampling
      4. 8.1.4 Magnetic Limit Check
      5. 8.1.5 Magnetic Threshold Band Cross Detection
      6. 8.1.6 Error Calculation During Linear Measurement
      7. 8.1.7 Error Calculation During Angular Measurement
    2. 8.2 Typical Applications
      1. 8.2.1 Angle Measurement
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Gain Adjustment for Angle Measurement
        3. 8.2.1.3 Application Curves
      2. 8.2.2 I2C Address Expansion
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Mechanical, Packaging, and Orderable Information

8.1.6 Error Calculation During Linear Measurement

The TMAG5173-Q1 offers independent configurations to perform linear position measurements in X, Y, and Z axes. To calculate the expected error during linear measurement, the contributions from each of the individual error sources must be understood. The relevant error sources include sensitivity error, offset, noise, cross axis sensitivity, hysteresis, nonlinearity, drift across temperature, drift across life time, and so forth. For a 3-axis Hall solution like the TMAG5173-Q1, the cross-axis sensitivity and hysteresis error sources are insignificant. Use Equation 19 to estimate the linear measurement error calculation at room temperature.

Equation 19. ErrorLM_25C=B×SENSER2+Boff2+NRMS_252B×100%

where

  • ErrorLM_25C is total error in % during linear measurement at 25°C.
  • B is input magnetic field.
  • SENSER is sensitivity error in decimal number at 25°C. As an example, enter 0.05 for sensitivity error of 5%.
  • Boff is offset error at 25°C.
  • NRMS_25 is RMS noise at 25°C.

In many applications, system level calibration at room temperature can nullify the offset and sensitivity errors at 25°C. The noise errors can be reduced by internally averaging by up to 32x on the device in addition to the averaging that could be done in the microcontroller. Use Equation 20 to estimate the linear measurement error across temperature after calibration at room temperature.

Equation 20. ErrorLM_Temp=B×SENSDR2+Boff_DR2+NRMS_Temp2B×100%

where

  • ErrorLM_Temp is total error in % during linear measurement across temperature after room temperature calibration.
  • B is input magnetic field.
  • SENSDR is sensitivity drift in decimal number from value at 25°C. As an example, enter 0.05 for sensitivity drift of 5%.
  • Boff_DR is offset drift from value at 25°C.
  • NRMS_Temp is RMS noise across temperature.

If room temperature calibration is not performed, sensitivity and offset errors at room temperature must also account for total error calculation across temperature (see Equation 21).

Equation 21. ErrorLM_Temp_NCal=B×SENSER2+B×SENSDR2+Boff2+Boff_DR2+NRMS_Temp2B×100%

where

  • ErrorLM_Temp_NCal is total error in % during linear measurement across temperature without room temperature calibration.
Note: In this section, error sources such as system mechanical vibration, magnet temperature gradient, earth magnetic field, nonlinearity, lifetime drift, and so forth, are not considered. The user must take these additional error sources into account while calculating overall system error budgets.