TIDUF97 September   2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 TMAG6180-Q1
      2. 2.3.2 MSPM0G3507
      3. 2.3.3 THVD1454
  9. 3System Design Theory
    1. 3.1 Hardware Design
      1. 3.1.1 Angle Sensor Schematic Design
      2. 3.1.2 MSPM0G3507 Schematic Design
      3. 3.1.3 RS485 Transceiver Schematic Design
      4. 3.1.4 Power Supply and Reference Voltage
    2. 3.2 Software Design
      1. 3.2.1 Angle Calculation Timing
      2. 3.2.2 Rotary Angle Calculation
      3. 3.2.3 Rotary Angle Error Sources and Compensation
      4. 3.2.4 Encoder Communication Interface
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 PCB Overview
      2. 4.1.2 Encoder and JTAG Interface
      3. 4.1.3 Software Requirements
    2. 4.2 Test Setup
    3. 4.3 Test Results
      1. 4.3.1 AMR Sensor Sin and Cos Outputs Measurement
      2. 4.3.2 Static Angle Noise Measurement
      3. 4.3.3 Rotary Angle Accuracy Measurement
        1. 4.3.3.1 Impact of Airgap on Noise, Harmonics, and Total Angle Accuracy
      4. 4.3.4 RS485 Interface and Signal Integrity
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 PCB Layout
      4. 5.1.4 Altium Project Files
      5. 5.1.5 Gerber Files
      6. 5.1.6 Assembly Drawings
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Authors

1.1 Key System Specifications

The key specifications of the TIDA-010947 high resolution low latency compact absolute angle encoder reference design with AMR sensor is provided in Table 1-1.

Table 1-1 Key Design Specifications
Parameter Value (Typical) Comment
Function Single-turn magnetic absolute angle encoder
Sensor type TMAG6180-Q1 high-precision analog AMR 360° angle sensor On-axis sensing
Magnet 13mm diameter, 1mm thick, Neodymium N52, Br = 1455 End of shaft mounted for on-axis sensing
Magnet to sensor placement End of shaft
Airgap 0.8mm Configurable
Angle accuracy error at 25°C ≤ 0.05° Offset and gain error calibrated at 25°C
Angle standard deviation ≤ 0.0033°
Angle resolution (standard deviation) 15.4 effective number of bits (ENOB)
Angle resolution (numerical) 32-bit (IQ21) Custom specific on MSPM0G3507
Angle propagation delay at 64-times oversampling (latency) 16 us Time from effective sampling point of magnetic field strength in x- and y-direction to angle calculated
Effective angle sample rate 32kHz
Operating speed ≤ 100000 rpm Not tested
A/D converter Dual 12-bit ADCs with 64-times hardware averaging Integrated to MSPM0G3507, ADC oversampling configurable up to 128-times
A/D converter oversampling rate 2.85 MSPS (250ns sample time, 100ns conversion time) Configurable sample time, 150ns minimum
Connector 5-pin, 1mm connector Refer to table 4-1
Interface RS485 THVD1454 half-duplex transceiver with Integrated 120Ω switchable termination
Supply voltage 5V ±10%
Supply current consumption 54mA Average current at 16kHz T-format command frequency
Operating temperature range -40°C to 125°C Reference design tested at 25°C ambient temperature
PCB diameter 30mm
PCB layers 4