Hi, I want to make a crystal oscillator using the IC cd4060.
However I don't have any of the 32Khz or 500Khz cyrstalls as shown in the datasheet.
I have 12.000Mhz crystal. I want to use this crystall to generate 1Hz signal. (I have few cd4060, if required). Since I can't find any lower Hz crystall, So, I should be using that 12Mhz crystal at any cost.
So, what I want to learn is what values of capacitor and resistor should I be using?
Also, Can a breadboard be used to trial the oscillator circuit? (I have heard somewhere that it won't work!)
A CD4060 has a max oscillator frequency of only 3.5MHz with a 5V supply and only 8MHz with a 10V supply. Use a 74HC04 to make an external 12MHz crystal oscillator but the CD4060 will not be able to use it for its counters. Use a 74HC4060 instead.
The datasheet for the crystal will list the recommended capacitor values including stray capacitance.
Why not just but the correct parts in the first place?
If you use a 32768Hz signal, with the CD4060, you'll get a 2Hz time base which can be divided by 2, to get 1Hz using a single flip-flop.
Ok, I went hunting for 3.2768kHz crystal. But at best I got 3.5748kHz. Can I use it instead ? If yes What is the corresponding values of capacitors and resistors?
What I really need is the correct formulas for the capacitors and resistors for a given crystal? Rest I can manage.
You can test it with the following circuit which will give a 2Hz output, add another flip-flop to divide that by 2 and you have your 1Hz timebase. **broken link removed**
You can test it with the following circuit which will give a 2Hz output, add another flip-flop to divide that by 2 and you have your 1Hz timebase. **broken link removed**
Thank you very much. Now I am all set to break up an old watch.
How much important are the Caps, and Resistor, however, I mean how much I can fluctuate them?
I believe I answered Mr Gibbs' comment but the post seems to have disappeared, I don't see why a moderator would've removed it because it was very polite.
Has the site been down or could it be my connection?
Anyway, another reason to use a watch crystal is that 32768Hz crystals tend to be more stable and accurate than other crystals for the same price. Watches and clocks have been designed to use 32768Hz crystals for years, for many reasons.