AD7147A

CapTouch Programmable Controller for Single-Electrode Capacitance Sensors AD7147A SWITCH MATRIX 06663-001 FEATURES Programmable capacitance-to-digital converter (CDC) Femtofarad (fF) resolution 13 capacitance sensor inputs 9 ms update rate, all 13 sensor inputs No external RC components required Automatic conversion sequencer On-chip automatic calibration logic Automatic compensation for environmental changes Automatic adaptive threshold and sensitivity levels Register map is compatible with the AD714x On-chip RAM to store calibration data Serial peripheral interface (SPI) (AD7147A) I2C-compatible serial interface (AD7147A-1) Separate VDRIVE level for serial interface Interrupt output and general-purpose input/output (GPIO) 25-ball, 2.3 mm × 2.1 mm WLCSP 2.6 V to 3.6 V supply voltage Low operating current Full power mode: 1 mA Low power mode: 28.96 μA APPLICATIONS Cell phones Personal music and multimedia players Smart handheld devices Television, A/V, and remote controls Gaming consoles Digital still cameras GENERAL DESCRIPTION The AD7147A CapTouch™ controller is designed for use with capacitance sensors implementing functions such as buttons, scroll bars, and wheels. The sensors need only one PCB layer, enabling ultrathin applications. The AD7147A is an integrated CDC with on-chip environmental calibration. The CDC has 13 inputs channeled through a switch matrix to a 16-bit, 250 kHz sigma-delta (Σ-Δ) converter. The CDC is capable of sensing changes in the capacitance of t...