Using Virtuoso Schematic Editor

in with the value of the variable. It is therefore incorrect to type in 3V for the valueof a voltage variable - CDS would interpret this to mean "3V" volts, which isundefined , rather than the "3" volts you intended.7. Printing a SchematicSelect Design->Plot from the main Schematic Editor menu, and set up forprinting as described under "Using the Cadence Design System". You will needto click on the Plot Options button in the dialog box that appears in order tochoose the printer type, plus other options.8. Saving a DesignYou can save a design from the Design menu, but the Cadence documentationrecommends that you always use Check and Save rather than just Save. Youcan also save the design under a different name (for later editing to make adifferent version, say), but note that the current file name stays what it was. So ifyou want to save to a new name, and edit that newly-named design, you will firsthave to open it by using Design->Open. This behaviour is different from mosteditors and programs you may be used to, so be careful you are working on theproperly named schematic.9. Creating a Symbol Cellview for Your DesignYou can "package'' your designed cell into a convenient module that has agraphical symbol (a "symbol''), which allows you to then incorporate it as a wholeinto another design schematic. For example, you could package an inverterdesign schematic named, say inv_small, containing an NMOS and a PMOStransistor into a normal inverter symbol (i.e. a triangular package with one input,and one output, with a bubble at the output).Before you can make the symbol cellview, you need to add "pins'' (from the Addmenu, or by using the pin tool on the toolbar) to define where the inputs andoutputs are. Then when you select Design->Create Cellview->FromCellview, a cellview editor opens allowing you to define the shape of thesymbol that will house your design, labels, etc.Now you could open a new design, and by picking inv_small from your library,drop in an instance that would appear as the triangular inverter symbol, havingterminals to which you will connect. By using this feature, you can build updesigns hierarchically, with simple logic cells having few transistors at the bottomof the hierarchy, and complex cells ( that contain simpler lower-level cells) at thetop of the hierarchy. You should already be familiar with this approach if youhave used the Altera Design software.