I need to know how to rotate between 3 outputs with a PBNO input using transistors. So each time I press the NO button it toggles the output between 1,2,3 then back to 1 and so forth. Any ideas???
I need to know how to rotate between 3 outputs with a PBNO input using transistors. So each time I press the NO button it toggles the output between 1,2,3 then back to 1 and so forth. Any ideas???
I should have looked at the data sheets first, but the IOH of the counter looks a little wimpy. You may need to put pullups on the Q outputs if you go with the ULN part.
Also, after you build the circuit and if you observe erratic behavior in the switch it may be a switch bounce problem. Eric did add switch debounce for the switch, but this may cause sloping edges which might cause the CMOS part to false trigger. If this happens you might want to put a schmidt trigger device in front of the counter input.
Here is a link that discusses switch bounce.