Hi everyone I am using PEX of different circuits and simulating it in top-level and running tran for 25u with 1u step, firstly it takes too much time understandably due to too many nodes and tracks it has to save data, secondly it get killed at 6u everytime no matter how small aur big step size is,what would be solution to not save these nodes and tracks rather save some specific nets I know I am using save all and it is causing this, how can I save only specific nets or output. One thing I know is to save data like for 20u to 25u using .tran 1 25u 20u

I would better check your extracted SPICE file. The capacitance values might be negative.