[Moved] Select a correct voltage controlled oscillator IC

[pequenochip]

I need to generate a sine signal using a VCO (voltage controlled oscillator) in order to feed a PLL (Phase-locked loop). I need the output to be 12.8MHz and 3.3Vp-p.

I bought at RS a VCO reference 7099357

Despite the datasheet says: "Output Level (CMOS) Output High (Logic “1”) - - 90% VDD" I can only have an output of 1.2Vp-p. Output frequency is 12.8 as expected. The IC is being feed with 3.3V DC.

What feature do I need to look at in order to select a componen that has the desired 3.3Vp-p output? Do you know any specific component I should use?

This is how I'm connecting the IC



**broken link removed**

 

[barry]

That device is a digital output (CMOS), not a sine-wave.

How are you measuring your output?

If you need your "output to be 12.8MHz", why do you need a VCO? If you really need a VCO, what's your frequency range? Accuracy?

 

[peterlarky]

Are you measuring with scope? how do you get a 1.2?
you should measure a 3.3v square wave on this circuit, it seems that you are measuring half of the amplitude, do you use any filter?