Digital Counter with 555 and 4026

[zawminoo]

I made a digital counter with 555 and 4026 ICs.
Simulation is OK.
When I construct it, it have a problem.
When I press switch S1, 7 Segment increase more than one.
For circuit, press switch S1, It must show 1, and then switch S1 again, it must show 2, and so on.
Now press switch S1, It is not stop at 1. It continue show until 5,6 or 7 .
How I correct this problem.
Please help me...Thank...

 

[bigdogguru]

You could be very well dealing with switch/contact bounce.

Unfortunately, simulations rarely take this issue into account.

Contact Bounce and De-Bouncing

How to de-bounce a switch using CMOS & TTL


BigDog

 

[IanP]

As it is the timer's time constant is roughly 0.15s.
t = 1.1 (R4+R6) C2
Try to increase the value of R4 or R6 so the time of the generated pulse is 0.5s or more ..

:wink:
IanP