Hello everyone,
I m trying to study the noise of a pulse oscillator I design on Ltspice but I reached the error "analysis failed: iteration limit reach"
Here is my schematic and the output of it:


But when I tried noise simulation the simulation fail and I don't know why:


Could you help me please.
I joined you the model of the inverter i used (SN74AHC04) from TexasInstrument and my Ltspice model.

Have a nice day

 

Maybe the "iteration limit reach" Is caused by the high frequency and extremely short pulse durations.
Why do you have 4 power supplies with no important decoupling capacitors?