The STM8T143 is the latest member of STMicroelectronics’ STM8T capacitive proximity and touch-key controller family embedding charge transfer capacitive technology. The STM8T143 measures human body capacitance near an electrode (usually made of a copper pad or conductive ITO material) behind a dielectric such as glass or acrylic panel.
The STM8T143 is a single-channel 8-pin device and has an extremely low current consumption (around 10 µA). The STM8T143 embeds sampling capacitors and a voltage regulator to optimize device sensitivity, as well as to improve system immunity in noisy environments. It offers a detection range up to 25 cm with its unique electrode parasitic-capacitance compensation (EPCC) feature.
In cell-phones, the STM8T143 provides on-ear proximity detection and deactivates the touchscreen function to prevent unintentional user touches during a call. The STM8T143 is also a unique solution to meet FCC SAR (specific absorption rate) requirements for tablets so as to reduce RF power when the device is in close contact with the user.
Other uses are various and include on/off switch replacement/enhancement, backlighting on proximity for user interfaces, wakeup or control functions on proximity, find-in-the-dark for lighting equipment, and companion devices for battery saving in portable equipment.
In addition, ST's touch-sensing library provides a complete, free source-code solution for capacitive touch-key controllers. The library allows designers acquainted with the use of standard microcontrollers to create higher-end human interfaces, by replacing conventional electromechanical switches by touch-sensing control. Designers can combine the touch-sensing function through multiple configurations (touch keys, wheels, sliders) with the traditional MCU features (communication, LED control, beeper, LCD control). The touch-sensing software library is part of the application firmware.
Type your request by:
