QST108 STMicroelectronics, QST108 Datasheet - Page 5

• Manufacturer Part Number: QST108
• Description: Capacitive Touch Sensor Device 8 Keys With Individual Key State Outputs Or I2c Interface
• Manufacturer: STMicroelectronics

QST108
1
Device overview
The QST108 capacitive touch sensor IC is a pure digital solution based on Quantum's
patented charge-transfer (QProx™) capacitive technology.
This technology allows users to create simple touch panel sensing electrode interfaces for
conventional or flexible printed circuit boards (PCB/FPCB). Sensing electrodes are part of
the PCB layout (copper pattern or printed conductive ink) and may be used in various
shapes (circle, rectangular, etc.).
By implementing the QProx™ charge-transfer algorithm, the QST108 detects finger
presence (human touch) near electrodes behind a dielectric (glass, plastic, wood, etc.). Only
one external sampling capacitor by channel is used in the measuring circuitry to control the
detection.
QST technology also incorporates advanced processing techniques such as drift
compensation, auto-calibration, noise filtering, and Quantum's patented Adjacent Key
Suppression™ (AKS™) to ensure maximum usability and control integrity.
In order to meet environmental requirements, ST offers this device in ECOPACK®
packages. These packages have a lead-free second level interconnect. The category of
second level interconnect is marked on the package and on the inner box label, in
compliance with JEDEC Standard JESD97.
The maximum ratings related to soldering conditions are also marked on the inner box label.
ECOPACK is an ST trademark. ECOPACK specifications are available at: www.st.com.
Device overview
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