GENERAL DESCRIPTION
The AD7143 is an integrated capacitance-to-digital converter (CDC) with on-chip environmental calibration for use in systems requiring a novel user input method. The AD7143 interfaces to external capacitance sensors implementing functions, such as capacitive buttons, scroll bars, and scroll wheels.
FEATURES
Programmable capacitance-to-digital converter
25 ms update rate (@ maximum sequence length)
Better than 1 fF resolution
8 capacitance sensor input channels
No external RC tuning components required
Automatic conversion sequencer
On-chip automatic calibration logic
Automatic compensation for environmental changes
Automatic adaptive threshold and sensitivity levels
On-chip RAM to store calibration data
I2C®-compatible serial interface
Separate VDRIVE level for serial interface
Interrupt output for host controller
16-lead, 4 mm x 4 mm LFCSP-VQ
2.6 V to 3.6 V supply voltage
Low operating current
Full power mode: less than 1 mA
Low power mode: 50 μA
APPLICATIONS
Personal music and multimedia players
Cell phones
Digital still cameras
Smart hand-held devices
Television, A/V, and remote controls
Gaming consoles