SNOSD15B December   2016  – April 2017 LDC2112 , LDC2114

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Digital Interface
    7. 6.7 I2C Interface
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Multi-Channel and Single-Channel Operation
      2. 7.3.2 Button Output Interfaces
      3. 7.3.3 Programmable Button Sensitivity
      4. 7.3.4 Baseline Tracking
      5. 7.3.5 Integrated Button Algorithms
      6. 7.3.6 I2C Interface
        1. 7.3.6.1 Selectable I2C Address (LDC2112 Only)
        2. 7.3.6.2 I2C Interface Specifications
        3. 7.3.6.3 I2C Bus Control
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Power Mode
      2. 7.4.2 Low Power Mode
      3. 7.4.3 Configuration Mode
    5. 7.5 Register Maps
      1. 7.5.1 Individual Register Listings
        1. 7.5.1.1 Gain Table for Registers GAIN0, GAIN1, GAIN2, and GAIN3
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1  Theory of Operation
      2. 8.1.2  Designing Sensor Parameters
      3. 8.1.3  Setting COM Pin Capacitor
      4. 8.1.4  Defining Power-On Timing
      5. 8.1.5  Configuring Button Scan Rate
      6. 8.1.6  Programming Button Sampling Window
      7. 8.1.7  Scaling Frequency Counter Output
      8. 8.1.8  Setting Button Triggering Threshold
      9. 8.1.9  Tracking Baseline
      10. 8.1.10 Mitigating False Button Detections
        1. 8.1.10.1 Eliminating Common-Mode Change (Anti-Common)
        2. 8.1.10.2 Resolving Simultaneous Button Presses (Max-Win)
        3. 8.1.10.3 Overcoming Case Twisting (Anti-Twist)
        4. 8.1.10.4 Mitigating Metal Deformation (Anti-Deform)
      11. 8.1.11 Reporting Interrupts for Button Presses and Error Conditions
      12. 8.1.12 Estimating Supply Current
    2. 8.2 Typical Application
      1. 8.2.1 Touch Button Design
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 DSBGA Light Sensitivity
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Related Links
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Export Control Notice
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • 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
  • Supports Independent Operation without MCU
  • 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

2 Applications

    Touch Buttons and Force Level Measurements on Different Materials, Including Metal, Plastic, and Glass for:

  • Consumer Electronics:
    • Smartphones
    • Smart Watches and Other Wearable Devices
    • Smart Speakers
    • Tablets/PCs
    • Virtual Reality Headsets
    • Sound Bars
  • Industrial Applications:
    • Televisions
    • Handheld Devices
    • Home Appliances
    • HMI Panels and Keypads

3 Description

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.

The LDC2112/LDC2114 is a multi-channel low-noise inductance to digital converter with integrated algorithms to implement inductive touch applications. The device employs an innovative LC resonator that offers high rejection of noise and interference. The LDC2112/LDC2114 can reliably detect material deflections of less than 200 nm.

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

The LDC2112/LDC2114 is available in a 16-pin DSBGA or TSSOP package. The 0.4 mm pitch DSBGA package has a very small 1.6 × 1.6 mm nominal body size with a maximum height of 0.4 mm. The 0.65 mm pitch TSSOP package has a 5.0 × 4.4 mm nominal body size with a maximum height of 1.2 mm.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
LDC2112/LDC2114 DSBGA (16) 1.6 mm × 1.6 mm
LDC2112/LDC2114 TSSOP (16) 5.0 mm × 4.4 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

LDC2112 LDC2114 ldc2114-simplified-schematic-ldc2114-version-snosd15.gif