Viewing Netlist Hierarchy and Netlist Flattening

003 : Viewing Netlist Hierarchy and Netlist Flattening

Minimum Required Version: Guardian LVS 4.8.36.R

Guardian LVS provides not only a netlist comparison function but also a netlist hierarchy viewing function and netlist flattening functions.

1. Netlist Hierarchy command

The Netlist Hierarchy command activates the Netlist Rover . The Netlist Rover is a tool for navigating through the netlist hierarchy, which is represented in the form of a tree.

To run the Netlist Hierarchy command:

1) Start Guardian LVS .

2) Set ring_osc.net as Netlist #1 in the Project Settings dialog ( Setup->Project Settings ). See lvs_ex03_set.png .

3) Activate Netlist #1 (select Window->First Netlist or click #1 icon). See ring_osc.net.

4) Run Netlist Hierarchy ( Action->Netlist Hierarchy ). The Netlist Rover window will appear. Click the Expand button to expand the hierarchy. Double-click "inv", and its definition in the netlist will be found and highlighted. See lvs_ex03_hview.png .

2. Flatten Netlist commands

The commands flatten any hierarchical netlist from the active window and put the result into a new window. The Hierarchical Names command generates a flattened netlist file with comments describing hierarchy transformation. Device and net names in the flat netlist hold information about the full path from the top level of the circuit hierarchy to the node. The Numbered Names command generates a flattened netlist with automatically-generated numbered names of devices and nets.

Running the Flatten Netlist commands:

1) Run Flatten Netlist with Hierarchy Names ( Action->Flatten Netlist->Hierarchical Names ). See ring_oscF_hrc.spice.

2) Run Flatten Netlist with Numbered Names ( Action->Flatten Netlist->Numbered Names ). See ring_oscF_num.spice.