AD7142 Programmable Controller for Capacitance Touch Sensors
The AD7142 and AD7142-1 are integrated capacitance-to-digital converters (CDCs) with on-chip environmental calibration for use in systems requiring a novel user input method. The AD7142 and AD7142-1 can interface to external capacitance sensors implementing functions such as capacitive buttons, scroll bars, or wheels. The CDC is capable of sensing changes in the capacitance of the external sensors and uses this information to register a sensor activation.
The AD7142 and AD7142-1 have on-chip calibration logic to account for changes in the ambient environment. The calibration sequence is performed automatically and at continuous intervals, when the sensors are not touched. This ensures that there are no false or nonregistering touches on the external sensors due to a changing environment.
The AD7142 has an SPI-compatible serial interface, and the AD7142-1 has an I2C-compatible serial interface. Both parts have an interrupt output, as well as a general-purpose input/ output (GPIO).
Applications
• Personal music and multimedia players
• Cell phones
• Digital still cameras
• Smart hand-held devices
• Television, A/V, and remote controls
• Gaming consoles
Advertisement
