saber890
Newbie level 6
varactor linearize
Hi all
Posted an similar question earlier, didnt get no reply, so still hoping theres help to be found.
What possibilities are there to increase the linearity in the tuning voltage to frequency transition, when an MOS variable gate-oxide capacitor is used??
I know that adding capacitances will "flatten" the capacitance vs tuning voltage C(V) curve of the varactor, but it will also decrease the tuning range, and that i want to avoid.
Also, i know that larger VCO output amplitude swings impact the effective varactor C(V) curve, averaging it more.
I have no means do specify the doping level of the varactor poly-gate, this is a process that influence the varactor linearity, but this option is not available.
AND, i would like to know how to measure the linearity for the varactor C(V) curve. I know the derivative should be a constant. Should a straight line be used as a reference? In that case, how do i implement it in the waveform window in cadence?
What other methods are there to increase the linearity?? are there other ways that the varactors can be configured, are there other ways to combine varactors that would help??
Hi all
Posted an similar question earlier, didnt get no reply, so still hoping theres help to be found.
What possibilities are there to increase the linearity in the tuning voltage to frequency transition, when an MOS variable gate-oxide capacitor is used??
I know that adding capacitances will "flatten" the capacitance vs tuning voltage C(V) curve of the varactor, but it will also decrease the tuning range, and that i want to avoid.
Also, i know that larger VCO output amplitude swings impact the effective varactor C(V) curve, averaging it more.
I have no means do specify the doping level of the varactor poly-gate, this is a process that influence the varactor linearity, but this option is not available.
AND, i would like to know how to measure the linearity for the varactor C(V) curve. I know the derivative should be a constant. Should a straight line be used as a reference? In that case, how do i implement it in the waveform window in cadence?
What other methods are there to increase the linearity?? are there other ways that the varactors can be configured, are there other ways to combine varactors that would help??