A simple solution for adding capacitive touch in new and legacy systems

A highly-integrated device that offers a simple solution for adding capacitive touch in new and legacy systems, Silicon Labs' CPT112S TouchXpress capacitive touch controller is now available from Mouser stock. Housed in a 3mm x 3mm QFN package, the device targets applications such as home appliances, instrument/control panels, medical equipment, consumer electronics, white goods and lighting control. The CPT112S controller supports up to 12 capacitive sensor inputs and uses an I²C interface to communicate to the host processor. As part of the TouchXpress family, the CPT112S is designed to easily replace mechanical buttons with capacitive touch buttons. The TouchXpress devices eliminate the need for firmware development, thereby decreasing the time it takes to deliver products to market. Designers can configure all the required capacitive touch sense parameters using a simple GUI-based configurator. Rated at 200µA in active mode and 1µA in sleep mode, the CPT112S controller quickly and easily delivers a low-power capacitive sense solution for embedded designs. Advanced features include wake-on proximity, moisture immunity, touch time-out, mutually-exclusive touch qualifier, buzzer feedback, and a slider control option. The I²C interface provides an easy way to track the status of touch sensors, and an interrupt pin can wake the host processor from sleep after a proximity touch detection.