design prescaler frequency

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haohaodk46

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Hi all !
I want make a prescaler about 3000 to divider frequency from 2.1Ghz.So how i can make it?
Thanks !
 

Do you want to implement it by yourself using with transistors?? Or will you use standard prescaler in the market ??
 

I want measure frequency VCO up to 2.1Ghz.But high frequency should not be measure direct by microcontroller,So I just need division frequency about 3000.
 

haohaodk46 said:
I want measure frequency VCO up to 2.1Ghz.But high frequency should not be measure direct by microcontroller,So I just need division frequency about 3000.
Click to expand...
Finding a divider circuit standalone is pretty difficult.There is a a bit more complex Integer/Fractional divider circuit by Hittite but I think it's expensive,I'm not sure..
If you intend to measure the "frequency only", why you don't use Mixer+VCO to obtain a lower frequency ?? It's more practical and there are many mixer and VCO circuits in the market.
You will obtain a primitive Spectrum Analyzer..Think about it...
 

Thanks you,but I dont understand why use Mixer + VCO to obtain a lower frequency.Can you explain or any document ?
 

haohaodk46 said:
Thanks you,but I dont understand why use Mixer + VCO to obtain a lower frequency.Can you explain or any document ?
Click to expand...
Simple..
You downconvert your VCO signal around-for instance 5MHz-and the you can measure the frequency of the main VCO.If you change the frequency,this IF will follow the changings.For example..

2.1GHz-->Mixer+Osc-->IF=5MHz so Osc frequency will be 2105MHz fixed.
2GHz -->Mixer+Osc-->IF=105MHz
1.9GHz-->Mixer+Osc-->IF=205MHz...
so on..
This IF frequencies can be measured easily by using ADC or modern ADC equipped Microcontollers..

Or you can use 2ndIF to decrease this frequency more..
 
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Thanks.With IF frequecny are 5,105,208 still too big to microcontroller can meaured.Perhap have use 2ndIF.But here matter how to creare a OSC frequency standard and upto 2105Mhz.
 

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