LDC2112/LDC2114 Inductive Touch Solutions

By Texas Instruments 53

LDC2112/LDC2114 Inductive Touch Solutions

Texas Instruments' LDC2112 and LDC2114 are multi-channel low-noise inductance to digital converters with integrated algorithms to implement inductive touch applications. Inductive sensing technology enables touch button design for human machine interface (HMI) on a wide variety of materials such as metal, glass, plastic, and wood, by measuring small deflections of conductive targets. The sensor for an inductive touch system is a coil that can be implemented on a small PCB located behind the panel and protected from the environment. Inductive sensing solution is insensitive to humidity or non-conductive contaminants such as oil and dirt. It is able to automatically correct for any deformation in the conductive targets.

Texas Instruments' LDC2112 and LDC2114 devices employ an innovative LC resonator that offers high rejection of noise and interference. They can reliably detect material deflections of less than 200 nm.

The LDC2112 and LDC2114 include an ultra-low power mode intended for power on/off buttons in battery powered applications.

The LDC2112 and LDC2114 are available in a 16-pin DSBGA or TSSOP package. The 0.4 mm pitch DSBGA package has a very small 1.6 mm x 1.6 mm nominal body size with a maximum height of 0.4 mm. The 0.65 mm pitch TSSOP package has a 5 mm x 4.4 mm nominal body size with a maximum height of 1.2 mm.

Applications include touch buttons and force level measurements on a variety of materials, including metal, plastic, and glass.

Features Applications
  • Low power consumption:
    • One button: 6 µA at 0.625 SPS
    • Two buttons: 72 µA at 20 SPS
  • Configurable button scan rates:
    • 0.625 SPS to 80 SPS
  • Force level measurement of touch buttons
  • Independent channel operation:
    • Two channels for LDC2112
    • Four channels for LDC2114
  • Integrated algorithms to enable:
    • Adjustable force threshold per button
    • Environmental shift compensation
    • Simultaneous button press detection
  • Robust EMI performance:
    • Allows for CISPR 22 and CISPR 24 compliance
  • Operating voltage range: 1.8 V ± 5%
  • Temperature range: -40°C to +85°C
  • Interface:
    • I2C
    • Dedicated logic output per channel
  • Consumer electronics:
    • Smartphones
    • Smart watches and other wearable devices
    • Smart speakers
    • Tablets/PCs
    • Virtual reality headsets
    • Sound bars
  • Industrial applications:
    • Televisions
    • Handheld devices

Categories

Top