AT42QT1111-MU

Introduction

The AT42QT1110 (QT1110) is a digital burst mode charge-transfer (QT™) capacitive sensor driver designed for any touch-key applications.
The keys can be constructed in different shapes and sizes. Refer to the Touch Sensors Design Guide and Application Note QTAN0002, Secrets of a Successful QTouch™ Design, for more information on construction and design methods (both downloadable from the Atmel® website).

Features

• Sensor Keys:
– Up to 11 QTouch™ channels
• Data Acquistion:
– Measurement of keys triggered either by a signal applied to the SYNC pin or at
regular intervals timed by the AT42QT1110s internal clock
– Keys measured sequentially for better performance, or in parallel groups for faster
operation
– Raw data for key touches can be read as a report over the SPI interface
• Discrete Outputs:
– Configurable “Detect” outputs indicating individual key touch (7-key mode)
• Device Setup:
– Device configuration can be stored in EEPROM
• Technology:
– Patented spread-spectrum charge-transfer (direct mode)
• Key Outline Sizes:
– 6 mm x 6 mm or larger (panel thickness dependent); widely different sizes and
shapes possible, including solid or ring shapes
• Key Spacings:
– 7 mm center to center or more (panel thickness dependent)
• Layers Required:
– One
• Electrode Materials:
– Etched copper, silver, carbon, Indium Tin Oxide (ITO)
• Electrode Substrates:
– PCB, FPCB, plastic films, glass
• Panel Materials:
– Plastic, glass, composites, painted surfaces (low particle density metallic paints
possible)
• Panel Thickness:
– Up to 10 mm glass, 5 mm plastic (electrode size dependent)
• Key Sensitivity:
– Individually settable via simple commands over serial interface
• Adjacent Key Suppression® (AKS™)
– Patented AKS technology to enable accurate key detection
• Interface:
– Full-duplex SPI slave mode (1.5 MHz), “change” pin, discrete detection outputs
• Moisture Tolerance Good
• Power:
– 3V ~ 5.5V
• Package:
– 32-pin 5 x 5 mm MLF RoHS compliant
– 32-pin 7 x 7 mm TQFP RoHS compliant
• Signal Processing:
– Self-calibration, auto drift compensation, noise filtering, AKS technology
• Applications:
– Consumer and industrial applications, such as TV, media player, etc