I want to design an analog circuit for the same.I want to know whether in the PLL (and by introducing a divider between VCO and Phase comparator)
the output of VCO would be a sinusoid.Because as far as I know the output is square.I could use an integrator to generate triangular wave at the same frequency as the o/p of VCO.But how do I get a sine wave from the triangular one.

Kindly tell me whether the approach is correct.Also send me a circuit of the sine shaper (that I would probably use to convert triangular to sine).

Thanks

 

If the oscillator is a sinewave one, then it's output will still be a sinewave, the divided down frequency fed in to the phase detector will be a square wave though.

You don't really give enough details on what you are trying to achieve, I'm presuming it may be a local oscillator for a radio, or something like that - where you need to lock a higher frequency oscillator to a lower reference frequency?.