TIDUES6 August   2020  – MONTH 

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 DRV8906-Q1
      2. 2.3.2 DRV8873-Q1
      3. 2.3.3 TPS1HB16-Q1
      4. 2.3.4 LM2904B-Q1
      5. 2.3.5 TLIN1028-Q1
    4. 2.4 System Design Theory
      1. 2.4.1 Mirror XY and LED Driver
      2. 2.4.2 Mirror Fold Driver
      3. 2.4.3 Mirror Heater Driver for Defogging and De-icing
      4. 2.4.4 Electrochromic Mirror Driver
        1. 2.4.4.1 Sallen-Key Low-Pass Filter
        2. 2.4.4.2 High-Current Buffer Amplifier
        3. 2.4.4.3 Buffer Amplifier Stability for Very-Large Capacitive Loads
        4. 2.4.4.4 Fast Discharge of Large Capacitive Load
      5. 2.4.5 SBC - LIN Communication Interface and System Supply
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
      1. 3.1.1 Hardware
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
      2. 3.2.2 Test Results
        1. 3.2.2.1 Reverse Battery Protection
        2. 3.2.2.2 X&Y Motors and LED Driver
        3. 3.2.2.3 Thermal Performance
  9. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 Altium Project
    4. 4.4 Gerber Files
    5. 4.5 Assembly Drawings
  10. 5Software Files
  11. 6Related Documentation
    1. 6.1 Trademarks
    2. 6.2 Third-Party Products Disclaimer
  12. 7Terminology

Thermal Performance

Thermal images of the TIDA-020027 board were taken under various operations to test the thermal performance of the board. The operations tested include operating the mirror folding motor, mirror heater, and the electrochromic mirror. The thermal images display the average and maximum temperature of the board.

Figure 3-8 shows the reference thermal image of the board connected to a power supply of 12.5 V with no loads being driven. The average temperature of the PCB is 25.5°C and the max temperature is 31.2°C.

Figure 3-9 is the thermal image while driving the mirror heater. The heater was driven to about a minute before taking the thermal image to allow the heater to reach its peak temperature. The average temperature of the PCB is 26.8°C and the maximum is 32.2°C.

Figure 3-10 shows the thermal image while driving the fold motor. The thermal image was taken while the fold motor was driven from one end to the other continuously. The max temperature of the board was measured at 31.7°C and the average temperature at 26.1°C.

Figure 3-11 is the thermal image of the PCB while driving the EC. The thermal image was taken once the mirror reached the programmed dimness level. The maximum temperature of the PCB was measured at 41.7°C which is concentrated around the Darlington BJT. The overall average temperature of the board is 28.4°C.

GUID-211817B4-9F4C-4D1C-BFD2-EC3F10346388-low.jpgFigure 3-8 Reference Thermal Image of PCB
GUID-82D7F304-9ED0-4A52-8F51-A4B9C5D34D2E-low.pngFigure 3-10 Thermal Image of PCB While Driving the Fold Motor
GUID-8AFEEFBE-6F9F-45E4-A1BC-913BA12A08E1-low.pngFigure 3-9 Thermal Image of PCB While Driving the Mirror Heater
GUID-58503B3A-6C7C-4AE8-A777-61663A7F96B1-low.pngFigure 3-11 Thermal Image of PCB While Driving the Electrochromic Mirror