Generating Pin to Trunk Routing for Selected Nets

When routing a complex design with many nets, it is ideal to use mesh and Pin to Trunk (P2T) routing to form clean routing structures effectively. For certain nets, Pin to Trunk (P2T) routing can be used, as required, where a trunk is first created on a certain layer and then the instance terminal pins is connected to these trunks. To do this:

Open a design in Layout MXL.
Open the Navigator assistant and select Objects – Nets.
Select a net in the Navigator assistant.
Choose Window – Assistants – Routing.
Alternatively, right-click anywhere on the layout window menu bar and choose Assistants – Routing.
(Optional) Click Delete to delete any routing on the selected net.
Select the scope of the mesh to be generated as either PR Boundary, Device Array/Fig Group or Area.
Select a layer from the Trunk layer drop-down list in the P2T section.
Click to select the Create trunks and Connect instances to trunks options to first generate the trunks and then connect the instance terminal pins to these trunks.

The router creates trunks and connects the trunks to the terminal pins of the instances on the selected net.
Click Generate P2T routing .
The router creates trunks and connects the trunks to the instances on the selected net. The two horizontal trunks are made and all pins on the devices are connected to the two trunks.

If there are two or more trunks created on the net, than to complete routing the net, the two trunks need to be connected. For this, use the mesh routing or finish routing to connect the multiple horizontal trunks. For more information, see Generating Mesh for Selected Nets.

Virtuoso Automated Device Placement and Routing Flow Guide
Product Version IC23.1, November 2023