vco cross coupled pair

I am trying to simulate a cross coupled VCO....however Cadence shows some strange warnings....
"M0: Vgd has exceeded the oxide breakdown voltage of `vbox' = 2.6 V"

Maybe this is because the amplitude of the resulting oscillation is close to 3V....whereas i expect it to be limited by the VDD which is 1.2V.....See the second figure for the PSS warning and resulting PSS waveform...

Can somebody help in solving this problem?

Regards

try to use the corss coupled pair NMOS and PMOS as well , i think this will reduce the amplitude of the singal , to the leve that will n't damaged the gate

i think this happens to u coz the DC point is ur VDD and then the SINE wave swing arround it , so the peak mey be high

but if u used the PMOS and NMOS architecture the gate bias will be VDD/2 ,

khouly