4066 Grounding Problem

[ksy]

Hey, I'm having a small problem with a circuit that I'm trying to build. I really don't know much (if anything) about electronics, I just kinda follow instructions Anyway, this circuit amplifies input from a piezo and closes a switch with the 4066. The problem I'm having is that the switch stays closed for a long period even after any signal is removed. However, if I ground the control pin on the 4066, the switch will immediately open up again. Again, I really have no clue about electronics, but I'm guessing the caps connected to the control pins are for grounding? Would choosing a smaller cap make the switch open up quicker or is the problem something else completely? Thanks.

 

[eblc1388]

I'm guessing the caps connected to the control pins are for grounding? Would choosing a smaller cap make the switch open up quicker or is the problem something else completely? Thanks.

Yes, it will. However, this is not a good way to control the timing.

The capacitors (C1~C4) store the charge from the diode and caused the long delay in opening.

You can control this behavior by placing a resistor in parallel to each capacitor.

**broken link removed**

A 100K value is a good start. This will shorten the delay to about 0.1~0.2 second. If the timing is not what you have wanted, you can use smaller or larger value resistors. A smaller value will cause the switch to open faster.