SBASAF4 September   2021 TMAG5170

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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 Magnetic Characteristics
    7. 6.7 Power up Timing
    8. 6.8 SPI Interface Timing
    9. 6.9 Typical Characteristics
  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 Magnetic Range Selection
      4. 7.3.4 Update Rate Settings
      5. 7.3.5 ALERT Function
        1. 7.3.5.1 Interrupt and Trigger Mode
        2. 7.3.5.2 Magnetic Switch Mode
      6. 7.3.6 Threshold Count
      7. 7.3.7 Diagnostics
        1. 7.3.7.1  Memory CRC Check
        2. 7.3.7.2  ALERT Integrity Check
        3. 7.3.7.3  VCC Check
        4. 7.3.7.4  Internal LDO Under Voltage Check
        5. 7.3.7.5  Digital Core Power-on Reset Check
        6. 7.3.7.6  SDO Output Check
        7. 7.3.7.7  Communication CRC Check
        8. 7.3.7.8  Oscillator Integrity Check
        9. 7.3.7.9  Magnetic Field Threshold Check
        10. 7.3.7.10 Temperature Alert Check
        11. 7.3.7.11 Analog Front-End (AFE) Check
        12. 7.3.7.12 Hall Resistance and Switch Matrix Check
        13. 7.3.7.13 Hall Offset Check
        14. 7.3.7.14 ADC Check
    4. 7.4 Device Functional Modes
      1. 7.4.1 Operating Modes
        1. 7.4.1.1 Active Mode
        2. 7.4.1.2 Standby Mode
        3. 7.4.1.3 Configuration Mode (DEFAULT)
        4. 7.4.1.4 Sleep Mode
        5. 7.4.1.5 Wake-Up and Sleep Mode
        6. 7.4.1.6 Deep-Sleep Mode
    5. 7.5 Programming
      1. 7.5.1 Data Definition
        1. 7.5.1.1 Magnetic Sensor Data
        2. 7.5.1.2 Temperature Sensor Data
        3. 7.5.1.3 Magnetic Sensor Offset Correction
        4. 7.5.1.4 Angle and Magnitude Data Definition
      2. 7.5.2 SPI Interface
        1. 7.5.2.1 SCK
        2. 7.5.2.2 CS
        3. 7.5.2.3 SDI
        4. 7.5.2.4 SDO
          1. 7.5.2.4.1 Regular 32-Bit SDO Read
          2. 7.5.2.4.2 Special 32-Bit SDO Read
        5. 7.5.2.5 SPI CRC
        6. 7.5.2.6 SPI Frame
          1. 7.5.2.6.1 32-Bit Read Frame
          2. 7.5.2.6.2 32-Bit Write Frame
    6. 7.6 Register Map
      1. 7.6.1 TMAG5170 Registers
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Selecting 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 Error Calculation During Linear Measurement
      5. 8.1.5 Error Calculation During Angular Measurement
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 Gain Adjustment for Angle Measurement
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Do's and Don'ts
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Detailed Design Procedure

For accurate angle measurement, the two axes amplitudes must be normalized by selecting the proper gain adjustment value in the MAG_GAN_CONFIG register. The gain adjustment value is a fractional decimal number between 0 and 1. The following steps must be followed to calculate this fractional value:

  1. Set the device at 32x average mode and rotate the shaft a full 360 degree.
  2. Record the two axes sensor ADC codes for the full 360 degree rotation.
  3. Measure the maximum peak-peak ADC code delta for each axis, Ax and Ay, as shown in Figure 8-6 or Figure 8-7.
  4. Calculate the gain adjustment value for X axis:
    Equation 18. GUID-5B83ADAC-3B41-4EDF-B1FA-E22C6EB2B4D5-low.gif
  5. If GX>1, apply the gain adjustment value to Y axis:
    Equation 19. GUID-C6E6ACBA-AB8C-45EF-8C1D-87AB1EFF84C4-low.gif
  6. Calculate the target binary gain setting at the GAIN_VALUE register bits:
    Equation 20. GX or GY = GAIN_VALUEdecimal / 1024

Example 1: If AX = AY = 60,000, the GAIN_SELECTION resister bits can be set as 00b. The GAIN_VALUE register bits are don't care bits in this case.

Example 2: If AX= 60,000, AY = 45,000, the GX = 45,000/60,000 =0.75. Select 01b for the GAIN_SELECTION register bits.

Example 3: If AX= 45,000, AY = 60,000, the GX = (60,000/45,000) =1.33. Since GX >1, the gain adjustment needs to be applied to Y axis with GY =1/GX. Select 10b for the GAIN_SELECTION register bits.