input capacitance of an inverter

[Chethan]

hi all,
can someone explain me how to find out the input capacitance of an inverter. What is the setup to find out the input capacitance. any material regarding the same would be very helpful.

thanx in advance
chethan

 

[flushrat]

add .option captab and find in .lis
or probe cap(node)

 

[mircea]

hi,

i am using cadence, so i don't know if this method is good for you, but here it is:

place a i source with idc=1A, simulate ac and then plot the 1/[val(vf(in))*2*pi*vf(in)]. use the cadence calculator. you can also use the clip function to have the results over a certain frequency range.

rgds,
M