QT1103-ISG

Overview

The QT1103-ISG is a 10-key capacitive touch sensor IC utilizing patented QTouch charge-transfer technology. It operates within a 2.8V to 5.0V supply range and features a 32-pin 5mm x 5mm QFN package. The device supports RS-232 based serial output with auto baud rate detection, offering single-wire or two-wire interface options. Key specifications include self-calibration, automatic drift compensation, and configurable adjacent key suppression (AKS). It provides low power operation modes for battery applications and includes fast detect capabilities for rapid response times.

Feature Summary

• Patented spread-spectrum charge-transfer sensing technology for robust noise immunity
• Integrated self-calibration and automatic drift compensation for stable long-term operation
• Configurable Adjacent Key Suppression (AKS) to prevent multi-touch errors
• Low power mode with selectable response times for battery-operated devices

Applications

• Portable consumer electronics
• Domestic appliances and A/V equipment
• PC peripherals and office equipment

Procurement Notes

Verify the specific ISG suffix configuration against the manufacturer's latest documentation to ensure compatibility with required AKS and LP mode settings. Confirm that the 32-QFN package dimensions align with the target PCB layout constraints. Ensure the host controller supports the required RS-232 serial protocol for data acquisition.

Selection Notes

Select this component when a high number of touch keys (up to 10) are required in a compact form factor. Consider the simplified mode if fewer option resistors are desired for reduced bill of materials complexity. Evaluate the need for AKS functionality based on panel thickness and key spacing requirements to determine appropriate resistor configurations.

Part Context

The QT1103 serves as a general replacement for the QT1101, offering improved sensitivity and lower power consumption. It eliminates the need for channel-specific Rs resistors found in previous generations. The device is part of the QTouch family, leveraging established charge-transfer algorithms for reliable capacitive sensing in various environmental conditions.

Replacement Considerations

The QT1103 is explicitly documented as a direct replacement for the QT1101. Designers should verify that the absence of Rs resistors in the QT1103 design does not require additional external components compared to the legacy QT1101 implementation.