20mhz crystal circuits
it is hard to control 50 -50 duty for different corner . you can serires a resister to
output circuit , adjust resister , you can get more gain , that you can gte better 50-50 in the corner process
Added after 2 minutes:
the simulation time , i add initial condition , and simulation about 200us for ss/tt/ff , high/low voltage , -40 , 125 . becasue some corner don't need 200us , but in the worst case , maybe 200us is need for simulation time