Schematic Tool Basics¶
After creating a netlist, the user may create a schematic by following the steps below:
If you have netlisted a library cell, such as a DFFR, you can view the schematic when that netlist is active (has a star by the name in the ‘Project Cells’ window):
Highlighting the cell in the ‘Project Cells’ window will take the user to the cell in the overlay:
Clicking on the ‘Show Schematics’ button on the ‘Schematic’ tab will bring up the schematic in the center pane:
Note:The schematic is initially rendered in the ‘auto layout’ mode. The work done in auto layout mode, i.e. rearranging the cells and output ports, is not saved when you close the window.
Right click in the Schematic and hover the mouse over ‘Schematic mode’ and click ‘Manual layout’
Right click again in the Schematic to bring up the context menu:
By clicking on ‘Place components using physical locations’ (after the schematic is in manual mode), the schematic will be reorganized to reflect the physical layout. This is especially useful for the library cell level and the analog case:
Click on a desired net, cell or port in the schematic window to select it. (Make sure the ‘select’ button is highlighted yellow). You will see the same object highlighted in the overlay.
Here is the overlay and schematic with a net highlighted:
Here is the overlay and schematic with a cell highlighted:
Here is the overlay with the ‘D’ port highlighted:
Larger Schematics¶
When you open a larger schematic, it will look more like this:
In general, the inputs are in the bottom left edge and the outputs are to the right edge. From here, it is recommended that the user right clicks in the window and sets the schematic mode to ‘manual layout’.
Zoom in to a closer view of the components, and select one (so it turns blue). Right click to pull up the context menu. Select Edit component.
The Edit Cell Instance window will appear:
Once you select a desired symbol, all of the cell instances are updated to reflect the change. Here you see the inverter symbol:
Select a group of related cells. They will all highlight in blue. Right click and select Move components to new block
Now the components are in one hierarchical block in the schematic:
Now click on the Block Creator in the Schematic Tab, check only the block that was just created, and switch your view to the overlay.
The corresponding cells are highlighted (in this case in a pink color) so the user can visualize the hierarchy.