Output of crystal oscillator.

[vetriselvan]

Dear all,
What is the output of the crystal oscillator.Is it sine or square wave.Then what is difference between CXO,VCXO,OCXo,TCXO.

Regards
Vetriselvan

 

[keith1200rs]

Re: Output of crytal oscillator.

It can be sine, square or "clipped sine" output. VCXO is voltage controlled - you can pull the frequency a little either side of nominal. TCXO us temperature compensated - pretty accurate with temperature. OCXO is an oven crystal oscillator. The crystal or whole circuit is in a temperature controlled oven. Very stable once up to temperature (which can take a while).

Keith.

 

[vetriselvan]

Dear Keith,
Thanks for ur post.
I need 10Mhz square wave from the crystal oscillator with 5V.
My doubt is shall i use the normal CXO or VCXO(voltage controlled oscillator).

Regards
Vetri

 

[keith1200rs]

Use a normal one - CXO. You would only ever use a VCXO in special applications, for example phase locking two clocks from different sources.

Keith.

 

[vetriselvan]

Thank you keith...
But i have tested one normal CXO.But it produced the sine wave.So only i have doubt in these..pls clarify...

Regards
Vetri.

 

[keith1200rs]

Have you a make & part number? It is likely that the one you bought produces a sine wave - you need to be careful to buy one with a square wave output. It would usually say TTL or CMOS output.

What bandwidth oscilloscope did you test it with? A low bandwidth oscilloscope will make a square wave look like a sine.

Keith bandwidth oscilloscope will make a square wave look like a sine.

Keith

 

[vetriselvan]

Der keith,
I forgot the part no & Make..I will reply you soon once i got it.I have checked with Textronics 200Mhz scope.

Regards
Vetri.

 

[vetriselvan]

Dear keith,
Hereby i have attached one datasheet.Please check and let me know whether the attached datasheet part no will provide the 10Mhz square wave with 5V.
DIGIKEY PART NO:CTX753-ND

Regards
Vetri

 

[mister_rf]

That's a clock oscillator HCMOS/TTL compatible = square wave output. :smile:

 

[vetriselvan]

Dear all,
Finally shall i use the part no in the datasheet.Plz suggest.

 

[keith1200rs]

If you are not seeing the output as a square wave then there is something wrong with either your oscillator or test setup. Have you a bandwidth limiter on the oscilloscope?

Keith.

 

[vetriselvan]

Dear keith,
I forgot the part no of the oscillator which i have tested.So i searched the new oscillator from DIGIKEY and the part no is CTX753-ND.the data sheet also attached above.So please let me know whether the above part no will give the square wave.

 

[keith1200rs]

Yes, the part number you linked to will give a square wave.

Keith.

 

[vetriselvan]

Hi all,
Thanks a lot for your support to me.

Regards
Vetri.

 

[rakirajueee08]

what had you did with this signal?