SNOSCY5B August 2014  – April 2015 FDC1004


  1. Features
  2. Applications
  3. Description
  4. Typical Application
  5. Revision History
  6. Pin Configuration and Functions
  7. Specifications
    1. 7.1Absolute Maximum Ratings
    2. 7.2ESD Ratings
    3. 7.3Recommended Operating Conditions
    4. 7.4Thermal Information
    5. 7.5Electrical Characteristicsnote to Electrical Characteristics table
    6. 7.6I2C Interface Voltage Level
    7. 7.7I2C Interface Timing
    8. 7.8Typical Characteristics
  8. Detailed Description
    1. 8.1Overview
    2. 8.2Functional Block Diagram
    3. 8.3Feature Description
      1. 8.3.1The Shield
      2. 8.3.2The CAPDAC
      3. 8.3.3Capacitive System Offset Calibration
      4. 8.3.4Capacitive Gain Calibration
    4. 8.4Device Functional Modes
      1. 8.4.1Single Ended Measurement
      2. 8.4.2Differential Measurement
    5. 8.5Programming
      1. 8.5.1Serial Bus Address
      2. 8.5.2Read/Write Operations
      3. 8.5.3Device Usage
        1. Configuration
        2. Measurements
        3. for Measurement Completion
        4. Read of Measurement Result
    6. 8.6Register Maps
      1. 8.6.1Registers
        1. Measurement Registers
      2. 8.6.2Measurement Configuration Registers
      3. 8.6.3FDC Configuration Register
      4. 8.6.4Offset Calibration Registers
      5. 8.6.5Gain Calibration Registers
      6. 8.6.6Manufacturer ID Register
      7. 8.6.7Device ID Register
  9. Applications and Implementation
    1. 9.1Application Information
      1. 9.1.1Liquid Level Sensor
    2. 9.2Typical Application
      1. 9.2.1Design Requirements
      2. 9.2.2Detailed Design Procedure
      3. 9.2.3Application Performance Plot
    3. 9.3Do's and Don'ts
    4. 9.4Initialization Set Up
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1Layout Guidelines
    2. 11.2Layout Example
  12. 12Device and Documentation Support
    1. 12.1Documentation Support
      1. 12.1.1Related Documentation
    2. 12.2Trademarks
    3. 12.3Electrostatic Discharge Caution
    4. 12.4Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Orderable Information

1 Features

  • Input Range: ±15 pF
  • Measurement Resolution: 0.5 fF
  • Maximum Offset Capacitance: 100 pF
  • Programmable Output Rates: 100/200/400 S/s
  • Maximum Shield Load: 400 pF
  • Supply Voltage: 3.3 V
  • Temp Range: –40° to 125°C
  • Current Consumption:
    • Active: 750 µA
    • Standby: 29 µA
  • Interface: I2C
  • Number of Channels: 4

2 Applications

  • Proximity Sensor
  • Gesture Recognition
  • Automotive Door / Kick Sensors
  • Automotive Rain Sensor
  • Remote and Direct Liquid Level Sensor
  • High-resolution Metal Profiling
  • Rain / Fog / Ice / Snow Sensor
  • Material Size Detection
  • Material Stack Height

3 Description

Capacitive sensing with grounded capacitor sensors is a very low-power, low-cost, high-resolution contact-less sensing technique that can be applied to a variety of applications ranging from proximity sensing and gesture recognition to material analysis and remote liquid level sensing. The sensor in a capacitive sensing system is any metal or conductor, allowing for low cost and highly flexible system design.

The FDC1004 is a high-resolution, 4-channel capacitance-to-digital converter for implementing capacitive sensing solutions. Each channel has a full scale range of ±15 pF and can handle a sensor offset capacitance of up to 100 pF, which can be either programmed internally or can be an external capacitor for tracking environmental changes over time and temperature. The large offset capacitance capability allows for the use of remote sensors.

The FDC1004 also includes shield drivers for sensor shields, which can reduce EMI interference and help focus the sensing direction of a capacitive sensor. The small footprint of the FDC1004 allows for use in space-constrained applications. The FDC1004 is available in a 10-pin WSON and VSSOP package and features an I2C interface for interfacing to an MCU.

Device Information(1)

FDC1004WSON (DSC)3.0 mm x 3.0 mm
VSSOP (DGS)3.0 mm x 3.0 mm
  1. For all available packages, see the orderable addendum at the end of the datasheet.

4 Typical Application

FDC1004 new_fig01_snoscy5.gif