QT1106-ISG

Overview

The QT1106-ISG is a capacitive touch controller IC based on the patented charge-transfer technology. It supports up to seven independent keys and one wheel or slider interface, enabling absolute position tracking for scroll wheels or linear sliders. The device operates within a voltage range of 2.8V to 5.0V and utilizes a five-wire SPI interface for communication with a host processor. Key features include self-calibration, drift compensation, and Adjacent Key Suppression (AKS) to ensure reliable operation in noisy environments. It is housed in a 32-pin 5x5mm QFN package.

Feature Summary

• Patented spread-spectrum charge-transfer technology for robust noise immunity
• Integrated self-calibration and automatic drift compensation mechanisms
• Configurable wheel and slider sensing with adjustable sensitivity via external capacitors or SPI commands
• Adjacent Key Suppression (AKS) prevents false triggers from closely spaced electrodes

Applications

• Portable electronic devices requiring intuitive user interfaces
• Domestic appliances and audio/video equipment controls
• PC peripherals such as mice and trackballs
• Office equipment with rotary encoders or linear sliders

Procurement Notes

Verify the specific suffix ISG confirms the operating temperature range of 0°C to +85°C and the 32-QFN tape and reel packaging configuration. Confirm RoHS compliance status through official manufacturer documentation prior to finalizing procurement orders.

Selection Notes

Select this component when designing interfaces that require both discrete buttons and continuous scrolling elements like wheels or sliders. Ensure the host system supports the required SPI protocol and can handle the CHANGE pin interrupt signals for efficient state polling without excessive processing overhead.

Part Context

This part belongs to the Quantum Research Group (QRG) family of capacitive sensing controllers, now integrated into Microchip Technology's portfolio. It represents an evolution of earlier QT series chips, offering enhanced signal processing capabilities and flexible layout options for various industrial and consumer applications.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Evaluate compatibility carefully if considering alternative capacitive touch controllers, as the proprietary charge-transfer algorithm and SPI command set may differ significantly.

FAQ

How does the QT1106 handle adjacent key interference?

The device employs a patented Adjacent Key Suppression (AKS) feature that compares signal strengths among grouped keys. It suppresses detections from weaker signals when a dominant touch is detected, preventing multiple keys from activating simultaneously.

Can the QT1106 detect hand proximity without touching?

Yes, Channel 7 can be configured as a QMagic Proximity Sensor. By adjusting the sample capacitor value and SPI settings, it can detect hand approach to trigger power-up or display activation without physical contact.

What is the maximum panel thickness supported for keys?

The device can sense through dielectric materials up to 10mm thick for standard keys. For wheel and slider configurations, the maximum recommended panel thickness is typically 4mm for glass and 3mm for plastic.