seekee

Hi. I'm currently working on a project and it requires debouncing circuit. I have a 74ls192 up down counter. The clock for the up and down pins will be push buttons. I need to have debouncing circuit for it.

Sebi

Choose one...

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bonxer

http://www.embedded.com/showArticle....cleID=18902552

Lots of reading and detail. At least there's pictures. Check out Figure 2: An RC debouncer. I personally never use R2, and I have never had bounce problems. Then again I'm not working on the shuttle either. 8)

Sebi

R2 reduce the discharge current, and prevent the switch erosion. When You have a 10A microswitch no problem if omitted.

bonxer

Of course then again, I'm the kind of guy that likes to charge capacitors up to around 35 volts or so and then strike the leads against a piece of metal to short, make it spark, and give a nice popping sound. The temorary welding effect is a bonus feature. :twisted:

ljcox

In order to ensure reliable operation, switch contacts need at least 5 Volt across them when open and at least 1 mA of current through them when closed.

This prevents the build up of an insulating film on the contact surfaces and therefore eventual failure.

Len

Juglenaut

Hex inverted with schmitt trigger. 7414 LS or better.

I also found that an AND gate works good, just tie one high and use the other input for the switch signal. HC series works best here.

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Random

Bumping a dead topic, sorry, but if one could make the circuit work with an inverted switch, would the NOT gate still be needed?

ljcox

I don't understand your question.

But this subject has been covered before, see for eaxmple http://www.electro-tech-online.com/v...nce+suppressor

Len