CapTouch™ Programmable Controller for Single-Electrode Capacitance Sensors
AD7147
FEATURES www.datasheet4u.com
Programm...
CapTouch™ Programmable Controller for Single-Electrode Capacitance Sensors
AD7147
FEATURES www.datasheet4u.com
Programmable capacitance-to-digital converter (CDC) Femtofarad 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 AD7142 On-chip RAM to store calibration data SPI-compatible (serial-peripheral-interface-compatible) serial interface (AD7147) I2C-compatible serial interface (AD7147-1) Separate VDRIVE level for serial interface Interrupt output and general-purpose input/output (GPIO) 24-lead, 4 mm × 4 mm LFCSP 2.6 V to 3.3 V supply
voltage Low operating current Full power mode: 1 mA Low power mode: 21.5 μA
FUNCTIONAL BLOCK DIAGRAM
ACSHIELD VCC
8 11
GND
10
BIAS
9
CIN0 19 CIN1 20 CIN2 21 CIN3 22 CIN4 23 EXCITATION SOURCE
POWER-ON RESET LOGIC
CIN6 1 CIN7 2 CIN8 3 CIN9 4 CIN10 5 CIN11 6 CIN12 7
SWITCH MATRIX
CIN5 24
AD7147
CALIBRATION RAM
16-BIT Σ-Δ CDC
CALIBRATION ENGINE
CONTROL AND DATA REGISTERS
VDRIVE 12
SERIAL INTERFACE AND CONTROL LOGIC
INTERRUPT AND GPIO LOGIC
18 GPIO
APPLICATIONS
Cell phones Personal music and multimedia players Smart handheld devices Television, A/V, and remote controls Gaming consoles Digital still cameras
SDO/ SDI/ SCLK CS/ SDA ADD0 ADD1
INT
Figure 1. AD7147 Bloc...