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):

DFFR1_ProjectCells

Highlighting the cell in the ‘Project Cells’ window will take the user to the cell in the overlay:

DFFR_in_overlay

Clicking on the ‘Show Schematics’ showschematics button on the ‘Schematic’ tab will bring up the schematic in the center pane:

ALS

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’

ManualLayout

Right click again in the Schematic to bring up the context menu:

schematic_Context

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:

DFFR_rearranged

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:

schematic_net_highlight

Here is the overlay and schematic with a cell highlighted:

schematic_cell_highlight

Here is the overlay with the ‘D’ port highlighted:

schematic_port_highlight

Larger Schematics

When you open a larger schematic, it will look more like this:

largerSchematic

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’.

ManualLayout

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.

SelectEditComponent

The Edit Cell Instance window will appear:

EditCellInstance

Once you select a desired symbol, all of the cell instances are updated to reflect the change. Here you see the inverter symbol:

InverterUpdate

Select a group of related cells. They will all highlight in blue. Right click and select Move components to new block

MoveToNewBlockContext

Now the components are in one hierarchical block in the schematic:

SchematicBlock

Now click on the Block Creator blockcreator in the Schematic Tab, check only the block that was just created, and switch your view to the overlay.

blocksinoverlay

The corresponding cells are highlighted (in this case in a pink color) so the user can visualize the hierarchy.