QT1080-IS48G

Overview

The QT1080-IS48G is an eight-channel capacitive touch sensor IC from the QTouch series, manufactured by Microchip Technology. It utilizes charge-transfer technology to detect touch or near-proximity on up to eight independent electrodes through dielectric materials. The device operates on a single supply voltage ranging from 2.8V to 5.0V and supports a commercial temperature range of -40°C to +85°C. It is housed in a 48-SSOP surface-mount package. Key electrical characteristics include a typical power consumption of 8mA during operation and approximately 45µA in low-power mode at 3V. The IC features built-in self-calibration, adjacent key suppression, and spread-spectrum noise rejection.

Feature Summary

• Supports eight independent sensing channels with individual sensitivity tuning via external capacitors.
• Includes Adjacent Key Suppression (AKS) to prevent false triggers from multiple simultaneous touches.
• Features continuous self-calibration and drift compensation for reliable long-term operation.
• Offers Spread-spectrum burst technology to minimize electromagnetic interference and emissions.

Applications

• Pointing devices
• Remote controls
• PC peripherals
• Television controls
• MP3 players

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm the specific IS48G suffix corresponds to the 48-SSOP package and industrial temperature rating. Check for End-of-Life status or obsolescence notices prior to procurement planning. Ensure compatibility with existing PCB footprints and design specifications.

Selection Notes

Select this model when eight dedicated touch inputs are required within a compact 48-pin SSOP footprint. Verify that the application environment falls within the specified -40°C to +85°C operating range. Ensure the system power supply remains stable between 2.8V and 5.0V to maintain proper calibration. Consider the simplified or full option resistor configurations based on output drive requirements.

Part Context

This component belongs to the Quantum QTouch family of capacitive touch controllers. It shares core charge-transfer sensing architecture with other models in the series but is distinguished by its eight-channel capacity and specific 48-SSOP packaging. It serves as a dedicated interface solution for replacing mechanical switches in human-machine interfaces.

Replacement Considerations

Direct pin-to-pin replacements may be limited due to the discontinued status. Evaluate alternative QTouch series members with similar channel counts and package types. Verify functional equivalence regarding AKS implementation and output modes before substitution.

FAQ

How does the device handle multiple simultaneous touches?

The QT1080 supports Adjacent Key Suppression (AKS), which can be configured to operate globally across all keys or in groups of four. In global mode, only the dominant key is detected; in group mode, up to two keys from different groups can be active simultaneously.

What is the function of the SYNC/LP pin?

The SYNC/LP pin serves dual purposes. It can accept an external sync signal to synchronize acquisition bursts with an external source like mains frequency, or it can trigger Low Power (LP) mode to reduce current consumption when no touch is detected.

How is sensitivity adjusted for each channel?

Sensitivity for each of the eight channels is tuned independently by connecting a sample capacitor (Cs) to the corresponding sense pins. Higher capacitance values generally increase sensitivity, allowing compensation for variations in key size or stray wiring capacitance.