Touch Sensor Capacitive 7 Key 1.8V to 5.5V Surface Mount 14-Pin SOIC Tube

The AT42QT1070 is a digital burst mode charge-transfer (QT) capacitive sensor driver. The device can sense from one to seven keys, dependent on mode. The QT1070 includes all signal processing functions necessary to provide stable sensing under a wide variety of changing conditions, and the outputs are fully debounced. Only a few external parts are required for operation and no external Cs capacitors are required. The QT1070 modulates its bursts in a spread-spectrum fashion in order to heavily suppress the effects of external noise, and to suppress RF emissions. The QT1070 uses a dual-pulse method of acquisition. This provides greater noise immunity and eliminates the need for external sampling capacitors, allowing touch sensing using a single pin.

• Comms mode
• Standalone mode
• Number of Keys:
• Comms mode: 1 – 7 keys (or 1 – 6 keys plus a Guard Channel)
• Standalone mode: 1 – 4 keys plus a fixed Guard Channel on key 0
• Number of I/O Lines:
• Standalone mode: 5 outputs
• Technology:
• Patented spread-spectrum charge-transfer
• Key Outline Sizes:
• 6 mm x 6 mm or larger (panel thickness dependent); widely different sizes and shapes possible
• Layers Required:
• One
• Electrode Materials:
• Etched copper; Silver; Carbon; Indium Tin Oxide (ITO)
• Panel Materials:
• Plastic; Glass; Composites; Painted surfaces (low particle density metallic paints possible
• Panel Thickness:
• Up to 10 mm glass; Up to 5 mm plastic (electrode size dependent)
• Key Sensitivity:
• Comms mode: individually settable via simple commands over I2 C-compatible interface
• Standalone mode: settings are fixed
• Interface:
• I²C-compatible slave mode (400 kHz). Discrete detection outputs
• Signal Processing:
• Self-calibration
• Auto drift compensation
• Noise filtering
• Adjacent Key Suppression® (AKS®) – up to three groups possible
• Power:
• 1.8 V – 5.5 V
• Package:
• 14-pin SOIC RoHS compliant IC
• 20-pin VQFN RoHS compliant IC