TIDUC26A April   2022  – April 2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Inductive Touch Buttons
      2. 2.2.2 Sensor Coil Placement
      3. 2.2.3 Collecting Data from Multiple LDCs
      4. 2.2.4 Magnetic Dial Implementation
      5. 2.2.5 CORDIC Algorithm
    3. 2.3 Highlighted Products
      1. 2.3.1 LDC3114-Q1
      2. 2.3.2 TMAG5273
      3. 2.3.3 DRV2605
      4. 2.3.4 TLV75518
      5. 2.3.5 TCA9534
      6. 2.3.6 PCA9543
      7. 2.3.7 Sensor Control Board
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Firmware and Programming
      1. 3.1.1 Operational Mode 1
      2. 3.1.2 Operational Mode 2
      3. 3.1.3 Operational Mode 3
    2. 3.2 Test Setup
    3. 3.3 Test Results
      1. 3.3.1 ABS Force Response
      2. 3.3.2 ABS Gain Corrected
      3. 3.3.3 Nylon Force Response
      4. 3.3.4 Nylon Gain Corrected
  10. 4Hardware Components
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6Revision History

3.1.1 Operational Mode 1

The reference design defaults into operational mode 1 on start-up. This mode uses the baseline tracking algorithm of the LDC3114 to implement eight different touch buttons. When each of these buttons are pressed, the digital output of the LDC3114s are monitored and correlate to an LED on the board. The digital outputs of the LDC3114 trigger when the baseline algorithm data gets higher than the button threshold. Once this happens, the pins on the device and the OUT register both show the button status as high depending on the polarity setting of the device. The LEDs used to show the button feed back only lights up one LED from a button press on each side of the board. This is because the MAXWIN feature of the LDC3114 is enables to prevent cases where two buttons on the same side can be pressed by putting hard enough on one button that the next button also triggers. Since this is applied by the LDC3114, a button press from each device can show on the LEDs at the same time. For more information on the internal algorithm of the LDC3114, see the LDC211x and LDC3114 Internal Algorithm Functionality application note. When in mode 1, pressing the magnetic dial button puts the operational mode into mode 2.