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Connecting Crystal Osscilators?

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grrr_arrghh

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Hi

i am trying to make an accurate clock, using a crystal and some cascaded 4017 or 4026 ICs

I can use 10, 16 or 18.432 MHz crystals. The diagram below shows how someone suggested I use the crystal. Could connect the bit marked output on the diagram straight to the input of the 4017/4026?

As my clock needs only to count up in 1/100s of a second, how would i divide/multiply the output of the crystal to get 100Hz?

All help greatly appreciated

Tim
 

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off the top of my head the easiest way to divide a clock is via using cascaded T-type's (toggle D-type registers) You can make a toggle from J-K flip-flop.

By using the output of yr clock as the toggle input to the first T-type. Use the 1st T-type output to be the 2nd T-types input. 2nd T-type output to third T-types input.

Keep this up. Each output will be a factor of 2 in frequency down from the previous output.


However you say you have a MHz range crystal.It will take alot of D-type to sub-divide. Why can't you use a 32kHz crystal. That is the standard value for timing?
 
oh, ok

thanks - the reason for the values was that they were just what i had to hand, but i can get a 32K if thats what u recomend.

what ICs have JK flip-flops in them? Also, any chance someone could draw me a quick diagram of how to connect them up? (i am in new teritory as far as electronics are conncerned)

How would i divide a 32K to get 100Hz (if divided by a factor of 2, closest I can get is 125Hz, or do I divide to 1000Hz, then divide by 10?)

Last question: if I used te diagrams above, and chose a 10M resistor that was spot on 10M, would the accuracy of the clock be limited to the accuracy of the crystal?

Thank you VERY much

Tim
 
Did you think of using CD4060 chip and 16.384MHz, 8.192MHz or 4.096MHZ crystals?
 
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