Capacitive sensor IC
Jon Baldwin of Texas Instruments says this will be easier and lower cost to design when you measure small changes in capacitance in a conductor rather than absolute capacitance levels.
Texas Instruments introduced a capacitive sensing IC, which it says can be used for automatic doors without the problems associated with sensing nearby objects or humans.
The FDC2214 senses small changes in capacitance and according to Baldwin this improves immunity to environmental noise from sources such as radios, power supplies, lights and motors.
Noise immunity is specified at 36dB.
The FDC2214 is designed to be insensitive to ambient light and can detect the presence of black and dark objects.
The sensor can be any conductor, such as copper on the printed circuit board (PCB), conductive ink or a piece of metal.
Source : Electronics Weekly
