Hi, All!

Hi, Steve,

>32K crystals in my experience need more than the usual inverter gate
>to get them going. Have you tried using 4000 series Cmos instead ?
>The higher transit delay makes it easier to set up a sustained oscillation.
No, I did not yet. It's needed to be ordered to be availeble on our stock.
How do you think about Schmitt-Triggered gates of this series, may it cause
a problem?

>You might find it better to design a simple Pierce Oscillator to get good
>low drift wrt temperature from your circuit.
>Steve
I am going to test the standard(transistor) Pierce Oscillator. But I sow
a HC04/4069 invertor based circuit that called as Pierce. Do you have a
positive experience with 32K on transistor Pierce Oscillator?
Thank you.

Hi, Cory,

>Use a higher frequency oscillator and divide it down to 32.768kHz. Choose
>your oscillator frequency carefully and divide carefully to ensure a 50%
>duty cycle.
>Another solution may be the oscillator products from Dallas Semiconductor
>or ICS.
>Cory Spackman
I have found an ICS - MK3200 - Clock Oscilator. Could you recomend me please
another simple devices if any please.
Thank you.


Hi, Charles,
>Try these following two sites
>http://www.ee.washington.edu/circuit_a...Schem.html
I have found here a really good theory description of the invertor based
oscilators. But even accuratly designed such circuit gives normal 32768Hz
oscillation on 100 PCBs and 10 are dead because of it.

>or
>http://members.aol.com/cpu8052
Could you refer me to 4060 device manufacturer to get the data sheet please.

>Both have schmatic's. One has a description of oscillators which is pretty
>good theory.
>Regards,
>Charles Bannister

Thank you.

Hi, Peter,

>the HC14 is the wrong device to build oscillators, since it has
>Schmitt-Trigger inputs.
>You must use the HC04, which work as analog amplifier near the threshold
>point.
Yes HC04 seems like more suitable. But even uCU's bult-in invertors withot
Schmitt-Trigger do not give a stable results. Are you sure the Sch-Tr
could cause additional unstability, since I need to use the Sch-Tr of the
device at another part of my circuit?

>For better accuracy and stability a true analog circuit was recommend,
>e.g. with a transistor or an operational amplifier.
>Peter
Yes, I am thinking about it.
Thank you.

Thanks again to All!
Best regards,
Oleg