The new IC draws only 31uA from a 1.8 VDC supply in a low power mode, enabling capacitive sensing to be added with less impact on battery lifetime. The AT42QT1040 is the new solution from company’s touch sensor division, that develops capacitive touch button, slider, wheel and touchscreen controllers. The new AT42QT1040 incorporates four digital output channels, allowing per-channel indication on touch detection. The new IC can also be configured utilizing one channel as a proximity sensor, allowing hidden-until-lit user interfaces where the device detects the presence of a finger some distance away from the keypad.
The new AT42QT1040 is based on Atmel’s QTouch charge-transfer sensing method. This technology utilizes spread-spectrum modulation to attain high immunity to electrical noise. The company’s Adjacent Key Suppression (AKS) technology, essential for tight-pitched keys, is utilized to ensure that only the intended key is activated by touch of a finger. Long-term reliability is attained because the device automatically calibrates on the power-up and always stays calibrated even if there is a build-up of moisture or other contaminants on the touch surface or if the overall system is subject to aging. Individual key sensitivity can be configured to support various front panel thicknesses and materials incorporating glass or plastic up to many millimeters thick. Electrodes can be made from the copper, silver, carbon, indium tin oxide (ITO) or any other conductive material. Broadly different electrode sizes and shapes are possible, giving product designer large flexibility to tailor the user interface. The new device has two power modes: a low power mode, which is ideal for small, battery-driven devices and a fast response mode, which offers minimum response time for the applications where low touch latency is necessary. To help product development the new AT42QT1040 has a debug mode in which internal data from the chip can be accessed. The ability to monitor the behavior of the device in this way means that designs can quickly be assessed and tuned resulting in a shorter product design time frame.
Availability and Pricing:
The new AT42QT1040 is available now in a space-saving 3mm x 3mm x 0.85mm package.
