diva
Newbie level 4
Hi all,
i want to know how to analyse this cross-couple delay cell's delay time for a ring oscillator.I want to find out its delay time in order to decision the VCO frequency , but I don’t know how to do the small signal analyse? If T ~ Rout*Ctot , how to find out Rout? It is a cross-couple logic cell,as Razavi says in his book, will presence negative resistor,-1/gm3。So the Rout = gds1//gds2//(-gm3) ? but it seem that the simulation result doesn’t support my view。So is anybody could tell me how to find out its delay time, how to make sure all the transitors’ size W/L
i want to know how to analyse this cross-couple delay cell's delay time for a ring oscillator.I want to find out its delay time in order to decision the VCO frequency , but I don’t know how to do the small signal analyse? If T ~ Rout*Ctot , how to find out Rout? It is a cross-couple logic cell,as Razavi says in his book, will presence negative resistor,-1/gm3。So the Rout = gds1//gds2//(-gm3) ? but it seem that the simulation result doesn’t support my view。So is anybody could tell me how to find out its delay time, how to make sure all the transitors’ size W/L
