Charge Transfer IC Can Detect Touch or Near Touch
The new QT110 from Quantum Research Group, offers a fully self-contained touch sensor that only requires a single capacitor to function.
It will project a sense field through almost any dielectric, like glass, plastic, stone, ceramic and most kinds of wood.
It can turn small metal bearing objects into intrinsic sensors, making them respond to proximity or touch. This capability coupled with its ability to self calibrate continuosly, makes this product
very stable and reliable.
The QT110 requries only a common inexpensive capacitor to function. A bare piezo beeper can be connected to create a 'tactile' feedback clicking sound; the beeper itself then doubles as the required
external capacitor, and it can be the sensing electrode.
Power consumption is under 20uA in most applications, allowing operation from Lithium batteries for many years. With a second capacitor the QT110 can be operated in 2-wirw mode, where both power and
signal traverse the same wire pair to the host.
The QT110's RISC core employs signal processing techniques pioneered by Quantum, these are specifically designed to make the device survive real-world challenges, such as 'stuck sensor' conditions and
The device includes several user-selectable built in features, such as Toggle mode for retaining state on switching. A Heartbeat signal is also provided for monitoring the health of the QT110.
The company's Web site address is http://www.qprox.com/.
[Reprinted with kind permission from Quantum Research Group Ltd]