QT  -  Series DataSheet
QT1103  -  QTOUCH? 10-KEY SENSOR IC  -  Atmel  -  Touch Technology

The QT1103 is designed for low cost appliance, mobile, and consumer electronics applications.
QTouch™ technology is a type of patented charge-transfer sensing method well known for its robust, stable, EMC-resistant characteristics.
It is the only all-digital capacitive sensing technology in the market today. This technology has over a decade of applications experience spanning thousands of designs.
QTouch circuits are renowned for simplicity, reliability, ease of design, and cost effectiveness.
QTouch™ sensors employ a single reference capacitor tied to two pins of the chip for each sensing key; a signal trace leads from one of the pins to the sensing electrode which forms the key. The sensing electrode can be a simple solid shape such as a rectangle or circle. An LED can be placed near or inside the solid circle for illumination.
The key electrodes can be designed into a conventional Printed Circuit Board (PCB) or Flexible Printed Circuit Board (FPCB) as a copper pattern, or as printed conductive ink on plastic film.

AT A GLANCE
Number of keys: 1 to 10
Technology: Patented spread-spectrum charge-transfer (one-per-key mode)
Key outline sizes: 5mm x 5mm or larger (panel thickness dependent); widely different sizes and shapes possible
Key spacings: 6mm or wider, center to center (panel thickness, human factors dependent)
Electrode design: Single solid or ring shaped electrodes; wide variety of possible layouts
Layers required: One layer substrate; electrodes and components can be on same side
Substrates: FR-4, low cost CEM-1 or FR-2 PCB materials; polyamide FPCB; PET films, glass
Electrode materials: Copper, silver, carbon, ITO, Orgacon† ink (virtually anything electrically conductive)
Panel materials: Plastic, glass, composites, painted surfaces (low particle density metallic paints possible)
Adjacent Metal: Compatible with grounded metal immediately next to keys
Panel thickness: Up to 50mm glass, 20mm plastic (key size dependent)
Key sensitivity: Settable via change in reference capacitor (Cs) value
Outputs: RS-232 based serial output, capable of single-wire operation
Moisture tolerance: Good
Power: 2.8V ~ 5.0V
Package: 32-pin 5 x 5mm QFN RoHS compliant
Signal processing: Self-calibration, auto drift compensation, noise filtering, AKS™
Applications: Portable devices, domestic appliances and A/V gear, PC peripherals, office equipment
Patents: AKS™ (patented Adjacent Key Suppression)
QTouch™ (patented Charge-transfer method)