JAJU837 March   2022

 

  1.   概要
  2.   Resources
  3.   特長
  4.   アプリケーション
  5.   5
  6. 1System Description
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products
      1. 2.2.1 TMAG5170
      2. 2.2.2 DRV5055A4
    3. 2.3 Design Considerations
      1. 2.3.1 Magnet Selection
      2. 2.3.2 Magnet Shape
      3. 2.3.3 Magnet Rotation Speed
      4. 2.3.4 Sensor Location
      5. 2.3.5 Expected Performance
      6. 2.3.6 Layout for Sensor Location
      7. 2.3.7 45° Alignment
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Test Setup
      1. 3.2.1 Test Equipment
      2. 3.2.2 Test Hardware Configuration
      3. 3.2.3 Test Software Configuration and Initial Data Capture
    3. 3.3 Test Results
      1. 3.3.1 Calibration Methods
      2. 3.3.2 TMAG5170 On-Axis
      3. 3.3.3 TMAG5170 In-Plane
      4. 3.3.4 TMAG5170 Off-Axis
      5. 3.3.5 TMAG5170 45° Alignment
      6. 3.3.6 DRV5055 Off Axis Result
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 サポート・リソース
    5. 4.5 Trademarks

3.3.5 TMAG5170 45° Alignment

As discussed in Design Considerations, the 45° alignment option dramatically reduces the need to adjust sensitivity gain by inherently matching the input magnitude observed for each axis. Some sensitivity mismatch may still be present, which might require minor adjustment.

This alignment was tested in the in-plane alignment at an identical range to the previous results. This alignment cannot use the CORDIC outputs from TMAG5170, given that it requires adjustment to the arctangent calculations to produce a useful result.

The resulting pre-calibrated error after performing phase correction is captured for this alignment and shown in 45° Angle Alignment Mechanical Angle Error

Figure 3-19 45° Angle Alignment Mechanical Angle Error
Table 3-5 45° Angle Alignment Harmonic Correction Factors
HARMONIC αi βi
1 –2.64 4.34
2 0.18 –5.59
3 0.82 0.51
4 –0.43 –0.05
5 0.06 –0.1
6 0 0.05
7 –0.025 –0.005

45° Calibrated Angle Error shows the resulting error after applying the harmonic data.

Figure 3-20 45° Calibrated Angle Error