SLYA048B March   2020  – June 2021 FDC1004 , FDC1004-Q1 , FDC2112 , FDC2112-Q1 , FDC2114 , FDC2114-Q1 , FDC2212 , FDC2212-Q1 , FDC2214 , FDC2214-Q1 , LDC0851 , LDC1001 , LDC1041 , LDC1051 , LDC1101 , LDC1312 , LDC1312-Q1 , LDC1314 , LDC1314-Q1 , LDC1612 , LDC1612-Q1 , LDC1614 , LDC1614-Q1 , LDC2112 , LDC2114 , LDC3114 , LDC3114-Q1

 

  1.   Trademarks
  2. 1Inductive and Capacitive Theory of Operation
    1. 1.1 Inductive Sensing Theory of Operation
    2. 1.2 Capacitive Sensing Theory of Operation
  3. 2FDC: Capacitive Level Sensing
    1. 2.1 Capacitive Technology Benefits in Liquid Level Sensing
    2. 2.2 Getting Started With Capacitive Liquid Level Sensing
    3. 2.3 Device Selection
    4. 2.4 Design Challenges and Additional Collateral
  4. 3LDC: Inductive Touch Buttons
    1. 3.1 Inductive Technology Benefits in Buttons
    2. 3.2 Getting Started With Inductive Buttons
    3. 3.3 Device Selection
    4. 3.4 Design Challenges and Additional Collateral
  5. 4LDC: Incremental Encoder and Event Counting
    1. 4.1 Inductive Technology Benefits in Incremental Encoders
    2. 4.2 Getting Started With an Inductive Incremental Encoder
    3. 4.3 Device Recommendations
    4. 4.4 Design Challenges and Additional Collateral
  6. 5LDC: Metal Proximity Sensor
    1. 5.1 Inductive Technology Benefits in Metal Proximity Detection
    2. 5.2 Criteria to Consider when Choosing Inductive Sensing for Metal Proximity Applications
      1. 5.2.1 Metal Target Movement in Relation to Inductive Coil
      2. 5.2.2 Sensing Distance
      3. 5.2.3 Size and Shape of Metal Target
      4. 5.2.4 Speed (Sample Rate versus Resolution)
      5. 5.2.5 Environmental Compensation
    3. 5.3 Getting Started With Inductive Metal Proximity Sensing
    4. 5.4 Device Recommendations
    5. 5.5 Design Challenges and Additional Collateral
  7. 6Revision History

2 FDC: Capacitive Level Sensing

Capacitive level sensing allows for a contactless method of level sensing, enabling a more robust solution compared to mechanical level sensors that can be prone to rust. TI’s capacitive level sensing solution incorporates an active shield driver that can reduce the external interference from foreign objects, such as a human hand. The engineer can use shield drivers using an out-of-phase technique to further stabilize the measurements and maximize the SNR.

Common applications include: wiper fluid and coolant level detection, coffee makers, refrigerators, small fuel tanks, and 3D printers.

GUID-F221A16D-BEF4-499A-8E83-5FF6C992DCDA-low.pngFigure 2-1 FDC Capacitive Level Sensing Application