Is it possible to do a Spectre sens analysis for a subcircuit? For instance having ..
subckt inv ( a b )
M1 ( a b vdd vdd ) pmos l=0.1u w=0.1u
M2 ( 0 b a 0 ) nmos l=0.1u w=0.1u
X1 (a b) inv
.. I'd like to get the sensitivity of the current I(X1:a) against the voltage of a. Using a line such as ..
sens ( X1:a ) to ( a ) for (dcOp )
.. gives the error message "`X1': Not a signal, device instance or a model."
Is there a way to achieve that?