AD7143

www.DataSheet4U.com Programmable Controller for Capacitance Touch Sensors AD7143 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 CIN0 15 CIN1 16 SWITCH MATRIX FUNCTIONAL BLOCK DIAGRAM AD7143 POWER-ON RESET LOGIC CIN2 1 CIN3 2 CIN4 3 CIN5 4 CIN6 5 CIN7 6 16-BIT Σ-Δ CDC CALIBRATION ENGINE CALIBRATION RAM 9 VCC CONTROL AND DATA REGISTERS 250kHz EXCITATION SOURCE 10 GND CSHIELD 7 SRC 8 I2C SERIAL INTERFACE AND CONTROL LOGIC 11 12 13 INTERRUPT LOGIC 14 06472-001 VDRIVE SDA SCLK INT Figure 1. APPLICATIONS Personal music and multimedia players Cell phones Digital still cameras Smart hand-held devices Television, A/V, and remote controls Gaming consoles 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 externa...