How to know that ALL MOS are in saturaion region by running ocean script?

If you're using OCEAN, and you've run a DC operating point simulation, then you can use the report() function to do this.

For example:

analysis('dc ?saveOppoint t)
run()
selectResult('dcOpInfo)
report(?param "region")

You'll get the region of each device returned as a number. If you look at "spectre -h modelType" - e.g. "spectre -h bsim4" you get:

 1       region=triode     Estimated operating region. Spectre outputs the number (0-4) in a rawfile.
                          Possible values are off, triode, sat, subth, and breakdown.

and for "spectre -h bjt" you get:

 3       region=fwd        Estimated operating region. Spectre outputs number (0-4) in a rawfile.
                          Possible values are off, fwd, rev, sat, and breakdown.

So the numbers correspond to the various regions. So for a MOS, 2 means it is in the saturation region.

The previous reply talking about CDF parameters is not relevant - that was (presumably) talking about the instance parameter region - which is merely a hint to the simulator as to which region the device is in, to help with DC convergence (an option that is rarely set, because it's not that practical to set it on each transistor, and anyway it's not the final region - just a clue to the simulator to tell it (say) that the device is off and hence to expect it to be off when trying to reach DC convergence).

Regards,

Andrew.

If you're using OCEAN, and you've run a DC operating point simulation, then you can use the report() function to do this.

For example:

analysis('dc ?saveOppoint t)
run()
selectResult('dcOpInfo)
report(?param "region")

You'll get the region of each device returned as a number. If you look at "spectre -h modelType" - e.g. "spectre -h bsim4" you get:

 1       region=triode     Estimated operating region. Spectre outputs the number (0-4) in a rawfile.
                          Possible values are off, triode, sat, subth, and breakdown.

and for "spectre -h bjt" you get:

 3       region=fwd        Estimated operating region. Spectre outputs number (0-4) in a rawfile.
                          Possible values are off, fwd, rev, sat, and breakdown.

So the numbers correspond to the various regions. So for a MOS, 2 means it is in the saturation region.

The previous reply talking about CDF parameters is not relevant - that was (presumably) talking about the instance parameter region - which is merely a hint to the simulator as to which region the device is in, to help with DC convergence (an option that is rarely set, because it's not that practical to set it on each transistor, and anyway it's not the final region - just a clue to the simulator to tell it (say) that the device is off and hence to expect it to be off when trying to reach DC convergence).

Regards,

Andrew.