These digital charge-transfer (“QT”) QMatrix™ ICs are designed to detect human touch on up to 16 or 24 keys when used with a scanned, passive X-Y matrix. They will project touch keys through almost any dielectric, e.g. glass, plastic, stone, ceramic, and even wood, up to thicknesses of 5 cm or more. The touch areas are defined as simple 2-part interdigitated electrodes of conductive material, like copper or screened silver or carbon deposited on the rear of a control panel. Key sizes, shapes and placement are almost entirely arbitrary; sizes and shapes of keys can be mixed within a single panel of keys and can vary by a factor of 20:1 in surface area. The sensitivity of each key can be set individually via simple functions over the serial port by a host microcontroller. Key setups are stored in an onboard eeprom and do not need to be reloaded with each powerup.

● Second generation charge-transfer QMatrix technology
● Keys individually adjustable for sensitivity, response time, and many other critical parameters
● Panel thicknesses to 50mm through any dielectric
● 16 and 24 touch key versions
● 100% autocal for life - no adjustments required
● SPI slave interface
● Adjacent key suppression feature
● Synchronous noise suppression feature
● Spread-spectrum modulation - high noise immunity
● Mix and match key sizes & shapes in one panel
● Low overhead communications protocol
● FMEA compliant design features
● Negligible external component count
● Extremely low cost per key
● +3 to +5V single supply operation
● 32-pin lead-free TQFP package

APPLICATIONS
● Security keypanels
● Industrial keyboards
● Appliance controls
● Outdoor keypads
● Appliance controls
● Outdoor keypads
● Automotive panels
● Machine tools