Simulation for hierarchical schematic

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Once we have finished schematic view of an inverter with the voltage sources as shown in the picture and have verified the functionality of it,  we are ready to make a symbol of this inverter for later use.

 

To make a symbol,  we need to first delete the voltage sources in the schematic, so there won't be any power supply within a symbol. This is quite important. We use the symbol comes with power supply, and when it is used in another circuit, there could be multiple supplys for one pin, and the simulation will fail.

Now we can create symbol for this schematic view. Select Design->Create Cellview-> From Cellview... there will be  symbol creation verification window as shown:

Make sure it is from schematic to symbol, then click on Apply and OK. A symbol will be created shortly. We can also edit the properties of the symbol, and give it a label name: "Inverter".

Finally, the inverter looks like this:

Save the work, and we are done with the inverter symbol.

Now it comes to how to use the symbol. Suppose we have a design(here, we call it INV_Test) which needs an inverter. We can select the symbol of this inverter from the library HW_1,  just as how we select an instance from standard libraries.

So this inverter is added on the current schematic view, and we can then provide voltage sources for it. They are the same two voltage sources we used for individual inverter simulation,  and the simulation steps are also going to be the same.  In this schematic view(INV_Test), we can also add other components if neccessary for a certain design.

If we want to take a look of the inside of the inverter, we need to select Design-> Hierarchy -> Descend Edit or Descend Read.