I experimented a bit with capacity based sensors and proximity detection. So I stumbled upon two very nice chips from Quantum Technologies: the QT113, a touch detection IC based on Kirchhoff’s Current Law and the QT301, a very interesting Capactiy-to-PWM (Pulse Width Modulation) IC.
The Sensor can be calibrated to a min an max value and now I’m going to find out how far away a stable detection can be sensored.
Definitely a nice toy – and regarding the prices for high quality push-buttons, the QT113 could be a nice alternative for mechanical switches.
More infos can be found at my second virtual home midibox.org
March 1st, 2007 at 18:50
I received a question about the circuit diagram.
It’s in the datasheet:
http://www.qprox.com/downloads/datasheets/qt301_106.pdf
November 7th, 2007 at 12:22
hi
where can we find qt301 chip ?
thank you
fab
November 7th, 2007 at 12:46
Hi,
I bought mine at http://www.farnell.com
(selling only for students & companies), but I’m sure other good sorted shops might have it as well. Depending on the country where you live, you might want to check out:
http://www.midibox.org/dokuwiki/where_to_order_components
Best,
Michael
November 10th, 2007 at 15:09
I just noticed that obviously it has gotten really hard to get this nice chip. Maybe I’m going to organize a batch order. For more informations, look here:
http://www.midibox.org/forum/index.php?topic=10162.msg76321#msg76321