Counter Reset

[chixdigit]

I'm using a CD4033 and I am trying to reset 2 seperate counter circuits once either one has hit 9.I'm sure I can do it if I had gates but at the moment I don't and I'd really like to get this done.So if anyone knows how or IF this can even be done I would really appreciate the help!

P.S
The count should go 0,1,...,8,9,0,1,...

 

[lord loh.]

I guess your counter has two reget terminals.... most of such counters do...

So you will have to connect Q3 and Q1 to these pins externally and it works...

I did it with 7490.

Could you post the datasheet?

 

[chixdigit]

Timing Diagram

I've basically come across a couple ways of doing it.The one way which I would like to do it I'm not exactly sure how to go about it.Mabey you can give me some pointers or suggestions.

Since the carry out sits high from 0-4 and low from 5-9. I was wondering if I could pulse the reset pin momentarly when it hits 0.The problem I am having is getting carry out to pulse and then go back low once it is finished.

The other way I could do it is use TTL but those use 5.5V and I am using a 12V source. Switching down to 5V and using an gate I think would be a lot more components then is needed.

But I am open to suggestions! Also the data sheet can be found at:
https://www.electro-tech-online.com/custompdfs/2006/03/cd4033.pdf

 

[Roff]

Have you tried a differentiator between Carry Out and Reset? Use a 1nF cap from CO to Rst, and a 10K resistor from Rst to GND. Add a 1N4148 diode in parallel with the resistor, anode to GND. This will give you a reset pulse of around 10usec width each time CO goes high. If your clock is faster than about 50kHz, that could be too long. You can shorten the pulse by making the cap or the resistor smaller. The minimum resistor value is probably about 4k, and the minimum capacitor value is about 100pF.
You mentioned using TTL. Why can't you do any required logic in CD4000 series? There is a complete set of gates, FFs, latches, MUXes. counters, registers, etc., available.

 

[chixdigit]

Newbie

Thank you so much Ron for all the advice! The differentiator that you mentioned sounds exactly what I am trying to do.I knew there was something that could do it but i didn't know what it was called or even where to start looking, tried google but without the name its hard to research As for the gates in the CD family I wasn't even aware they existed. Haha ahhh....I guess thats why I have the newbie tag and you have the God tag.

Again I really appreciate it, I can not thank you guys enough for all the help you give!

 

[chixdigit]

Newbie

Ron my man...<standing slow clap> I don't even know where to begin...utterly speechless. I cannot thank you enough!

 

[Roff]

Re: Newbie

Ron my man...<standing slow clap> I don't even know where to begin...utterly speechless. I cannot thank you enough!

Can we assume this means it worked? :lol:

BTW, I don't want the standing slow clap.... I had to take penicillin once to get rid of it. :lol: