Digital clock (need some help)

[swiz747]

Hi,
I have been recently assigned a digital "clock" project that has very simple requirements (needed to count to 59 seconds and reset to 0) but I as the over achiever that I am decided to go way above and beyond the requirements for this. I have drawn up some schematics for a true 12 hour clock that uses the 60Hz from a wall line for a clock pulse but then I wanted to go one step above that so I looked into crystal oscillators and found that I could use a 32.678K Hz crystal but I couldn't find out how to implement it into my circuit. I know I have to use a divider to get a 1Hz pulse but I cant find a circuit to use the crystal. I'm assuming that there's some kind of circuit to utilize it based on the little information I've found on it. Anyway I'd just like to thank you for any help you could give this student that bit off more than he could chew.

 

[dougy83]

Have a look at the 4060 - it's a divider chip with built-in oscillator circuit (connect your xtal to it) designed for your purpose. Schematics should be in the datasheet

 

[swiz747]

Thanks for your help! my only problem with the 4060 is that its a CMOS IC, is there any TTL IC thats similar? If not I'll use it. thanks again for your help

 

[MikeMl]

4000 series CMOS is much nicer, easier to work with compared to that 7400 dinosaur

 

[dougy83]

CMOS outputs are compatible with TTL inputs if that's what you're concerned about.

 

[shaun rowland]

4000 j/y crystal occilator not sure if i spelt tht right but i think thts what you want