prprog
Member
The sensor is formed by a series of copper trace that do not touch. A resistance material is put over the sensor so, when it is press the resistance is lower and a voltage generated and detected by the Comparator (LM339).
The voltage activates the 4066 analog switch. If I don't used the .047uf capacitor the switching is unreliable. It fluctuates on-off.
With the .047uf cap it works better. It doesn’t fluctuate...but the switching is not fast enough. [I try a small Capacitor value and the erratic on-off behavior continues. A large cap value takes to long to activate the switch. (The 4066 substitutes a piano keyboard - this is how I know that its behavior is not fast enough). I believed this is because of the charging/discharge time of the cap. What can I do to make it switch faster?
(the control input lines off the 4066 are connected to ground. Also the inputs of the LM339.)
Thanks,
The voltage activates the 4066 analog switch. If I don't used the .047uf capacitor the switching is unreliable. It fluctuates on-off.
With the .047uf cap it works better. It doesn’t fluctuate...but the switching is not fast enough. [I try a small Capacitor value and the erratic on-off behavior continues. A large cap value takes to long to activate the switch. (The 4066 substitutes a piano keyboard - this is how I know that its behavior is not fast enough). I believed this is because of the charging/discharge time of the cap. What can I do to make it switch faster?
(the control input lines off the 4066 are connected to ground. Also the inputs of the LM339.)
Thanks,
Attachments
Last edited: