Defining Bind-to-Open on a Per-Instance Basis

You can specify that a single instantiation of a cell is to be skipped by setting a bind-to-open attribute on it.

Only non-text instances, such as schematic instances can be skipped using bind-to-open. Bind-to-open should not be set on hierarchical text instances.

A bind-to-open attribute on an instance can apply to multiple objects—if the cell that contains the instance is used in multiple places in the design, the bind-to-open applies to the instance in all those places. For example, if you specify that instance I2 in cell OpAmp is unbound and cell OpAmp is used in three places in the design, I2 gets unbound in all three instantiations of OpAmp.

The Hierarchy Editor displays the string **UNBOUND** to indicate that an instance has a bind-to-open attribute. **UNBOUND** is not an error, unlike **NONE**. **UNBOUND** indicates that the instance is deliberately unbound while **NONE** indicates that the binding for the instance could not be determined from the binding rules.

You can add a bind-to-open attribute to an instance from either the tree view or the table view of the Hierarchy Editor.

To add a bind-to-open attribute to an instance from the tree view,

Choose View – Tree to display the tree view of the configuration, if it is not already displayed.
If the Occurrence Mode button on the toolbar is selected, deselect it.
The tree view now displays Target: Instance.
Right-click the instance on which you want to add a bind-to-open.
From the pop-up menu, select Add Bind To Open (Skip Instance).

In case multiple rows are selected, the pop-up menu displays the Add Bind To Open (Skip Multiple) option.

The instance is now unbound. The library, cell, and view name of the instance are replaced by **UNBOUND**. For example:

If the instance has already been identified as an occurrence and the tree view displays Target: Occurrence when the instance is selected, the bind-to-open attribute is applied to the occurrence.

To add a bind-to-open attribute to an instance from the table view,

Choose View – Parts Table and View – Instance Table to display the table view of the configuration, if it is not already displayed.
In the Cell Bindings section, select the cell that contains the instance to which you want to add a bind-to-open attribute.
The Instance Bindings section displays the instances contained in the cell.
In the Instance Bindings section, right-click the instance to which you want to add a bind-to-open.
From the pop-up menu, select Add Bind To Open (Skip Instance).
The instance is now unbound. The Library, Cell, View Found, and View to Use columns display **UNBOUND**. For example:

If the cellview that contains the instance is used in multiple places in the design, the bind-to-open applies to the instance in all those places.

To see which objects the bind-to-open applies to,

In the Cell Bindings section, right-click the cell that contains the instance to which you added the bind-to-open.
From the pop-up menu, select Explain.
The Explain dialog box appears. The Instantiations section lists the instantiations of the cell. The bind-to-open applies to the instance in all these instantiations of the cell. If any of the instances has an occurrence binding on it already, the bind-to-open does not apply to it.

Virtuoso Hierarchy Editor User Guide
Product Version IC23.1, August 2023