Varactor voltage by thermistor voltage divider. Is it normal solution?

[Terminator3]

What if prescaler circuity gives too much precision, can it be replaced by thermistor voltage-divider before varactor? I think curve can be approximated by thermistor. Actually i worry about active device, maybe there some "aging" of it capacitance, etc., so thermistor will give wrong correction after some time... when device change it frequency curve over temperature.

 

[FvM]

I wonder if it might be possible to phrase an understandable question from this line up of terms?

 

[Terminator3]

does active device parasitics, capacitance, etc. change over time? all that things that can influence frequency. p.s. somebody sure can phrase a whole patent in such terms

 

[BigBoss]

You can surely use thermistor but tuning voltage is almost constant and it does not create a trouble.
The main effects come from other temperature sensitive components and they can not be easily tolerated and compansated.
For instance, temperature dependency of a intrinsic capacitor can not be compansated in any manner, in this case what does it make sense to tolerate tuning voltage by using thermistor ??
Nope..
Frequency stability of a VCO can be handled by a simply well designed PLL.