on which parameter the output frequency of VCO in pll depends

i am fresher in this field, Can anybody tell me what parameter defines the final output frequency of vco in pll.

suppose i want to design a pll to give output frequency of 100MHz, this is the frequency to which pll has to lock,
i m using 10 MHz reference, then which parameter i have to set to get this output frequency.
but where i have to define this frequency.

i have gone through the SimPLL of analog devices, but not able to find out answer.

You can put a divide-by-10 counter in the feedback path, to multiply your 10MHz to 100Mhz.

hi
please study this tutorial

arunsharma0731 said:

i am fresher in this field, Can anybody tell me what parameter defines the final output frequency of vco in pll.

suppose i want to design a pll to give output frequency of 100MHz, this is the frequency to which pll has to lock,
i m using 10 MHz reference, then which parameter i have to set to get this output frequency.
but where i have to define this frequency.

i have gone through the SimPLL of analog devices, but not able to find out answer.

Click to expand...

You will find your answer in the datasheet of th PLL which you want to use.
Because every PLL has different programming features and type.
Look at "programming chapter" of the datasheet...

arunsharma0731 said:

i am fresher in this field, Can anybody tell me what parameter defines the final output frequency of vco in pll.

suppose i want to design a pll to give output frequency of 100MHz, this is the frequency to which pll has to lock,
i m using 10 MHz reference, then which parameter i have to set to get this output frequency.
but where i have to define this frequency.

i have gone through the SimPLL of analog devices, but not able to find out answer.

Click to expand...

All of them really.
But the VCO (Voltage Control Oscillator) is where you will get the "Output Frequency" .

If you have a discreet component design you can disconnect the Loop Filter and
put a voltage on the V-Tune line of the VCO to see how it changes the Output
Freq with Voltage.

You have to make sure your VCO can work at 100MHz.

As for your Spec's Ref=10MHz , then your divider needs to be N=10.

RF=100MHz.
Ref = RF/N

Also (Unless you have a integrated PLL/VCO) you will need to make sure all your
components are capable of working together. i.e. if LoopFilter requires 10mA Drive
and your Charge Pump on can provide 4mA, you have an issues. And you have to
make sure your Feed back path for the RF is not loading down the VCXO so it stops operating.

Also before you post a Questions, search the Board first. Your Question has most
likely been answered .

https://www.edaboard.com/threads/144053/

Cheers