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The whole ADE annotation flow was overhauled way back in IC6.1.6 but at that time there was no way to share the annotation settings between designs, or to automatically load them. Well, in IC6.1.7 ISR13 we have added the ability to do both!
Maybe you have a few existing annotation setup files, perhaps one for components from a certain PDK or maybe separate ones for different components? If you've been loading in annotation setups in ADE, you'll know there was no way to do this automatically and you had to load them in manually through the Annotation Setup form.
You'll also have noticed that the annotation setup files could not be shared, they were tied to a lib/cell/view.
Well, now you can specify the paths to your annotation files in your .cdsinit file and they will be automatically loaded when the design opens in the schematic window. You can also share them between designs.
Let's take an example, to see how this works. Let's say you have some annotation setup files already saved in your .cadence directory that you want to share with another design. You'll find the annotation files under .cadence/dfII/annotationSetups/<Lib>/<Cell>/<View>/
All that you have to do to use these files in another design is to simply copy them to another area under your .cadence directory that does not contain a lib/cell/view structure, such as .cadence/dfII/annotationSetups.
Set the following environment variables in your .cdsinit file, specifying the paths to your annotation files and these will be loaded when you start up Virtuoso. In this example, I have added annotation settings for the resnsppoly and mimcap cells.
The Load and Save Annotation Setup forms have a new button, Load from Absolute Path and Save at Absolute Path. If you choose to load from or save at absolute path, the annotation setup files will be saved or loaded from the .cadence directory you specify. If you choose not to load from or save at the absolute path, Virtuoso will look for annotations under the .cadence you choose, but under the lib/cell/view. So, these annotations cannot be shared.
Using bindkeys to toggle the annotations on the schematic makes it quick and easy to show the different results — just with the press of a key.
If you've run a simulation that carried out a DC and a transient simulation, and you've saved different annotations settings for each analysis, you can press the bindkeys to toggle between the two annotations. The DC annotations would show the DC voltage and currents for the terminals, and the DC operating points gm, id, vsat_marg, vdsat and self gain. The transient annotations will display the transient voltages and currents for the terminals, and also the vgs, ids, vds and vdsat transient operating points.
So the settings are like this:
Then if we assign bindkeys to each of these, then you can toggle the annotations on the schematic without having to open the form. Double check which bindkeys are free, use the CIW->Options->Bindkeys to confirm. In this example, I've set Ctrl+Shift+J to load the DC annotation settings, and Ctrl+Shift+M to load the Transient annotation settings.
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