Plotting Device Parameters (gm, vdsat, etc) Vs Time or Temp


I feel like this has gotten more complicated. I think it might have been easier 10 years ago. Then again, I could be w.

Go to resource: How to save and plot operating point parameters for Spectre simulator from ADE Explorer/Assembler

In Explorer, you go to Outputs > To be Saved > Select OP Parameters


Now, the schematic window is active and you can click on instances and each gets highlighted as you do.

These get populated in the Assembler Outputs Setup

You will see that the "Type" is not signal but oppoint.

If you click on the Details field, it splits into two - the /whatever/deviceName is on the left, and on the new field on the right, you can enter parameters appropriate for that device, like vdsat, vth, cgs, etc. 


The UI is very poor, but, on the right of this field is a button you can actually click to choose from a list. It'll even run a sim if necessary!

If you want these plotted, you have to check the box to the right under the Plot column.

Other gems

Finding all Operating Point parameters available for a certain device type : $ spectre -h bsim4 # example

What if you wanted to run a long simulation once, and, from that simulation, save the operating point info from a few timepoints with the aim of using one of those as a starting point later, to save time? A: With TRAN options, specify infotimes and infonames. You'll have to specify filenames for "where". You can read those in later with the readns/readic options


BTW, if you're not benefiting from the productivity setup using 100+ custom keyboard shortcuts (bindkeys), be sure to check those out.

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