Virtuoso Schematic Composer User Guide

Editing Objects

The User Preferences form appears.

2.Move the Undo Limit slider to the limit you want.

3.Click OK.

Stretching

Use the Stretch command to reposition the placement of objects in your design without losing connectivity between wires and pins.

■Stretching works most easily when infix mode is turned on.

■Direct manipulation is the easiest and fastest way to stretch objects or shapes.

■The Stretch command does not stretch objects from one cellview to another.

■Use extended selection to select an object (such as an instance, pin, or block) and associated wires so you can stretch them all at once.

The Stretch command operates differently in the schematic editor and the symbol editor.

In the schematic editor, Stretch

■Stretches selected objects and maintains connectivity by rerouting wires when necessary

The Stretch command supports partially selected wire vertexes. The remaining nonselected vertexes are anchored in place.

Virtuoso Schematic Composer User Guide

Editing Objects

■Moves wires while maintaining connectivity with the object attached to the wire

■Moves a pin while maintaining connectivity with the wire that is attached to the pin

In the symbol editor, Stretch

■Stretches an entire shape

Shapes move independently of one another. They do not need to maintain connectivity.

■Stretches a partial shape (an edge or a vertex of a shape or an endpoint of a line)

Stretching with the Schematic Editor

To stretch an object using the schematic editor, do the following:

1.Choose Edit – Stretch.

2.Select the object you want to stretch.

The point used to select the object becomes the reference point.

3.Point at a reference point.

4.Move the mouse, then click a destination for the stretch.

5.To change Stretch command options, press F3. The Stretch form appears.

Virtuoso Schematic Composer User Guide

Editing Objects

Note: If you select objects other than instances, wires, or schematic pins, they move instead of stretch.

The following sections describe using the Stretch command on various objects.

Stretching an Instance

The following diagram shows how to stretch an instance using the schematic editor default settings.

inv

During the stretch process

IO

A Y

inv

After stretching an

instance IO A Y

inv

To reroute wire segments, do the following:

On the Stretch form, turn on Reroute Wire Segments Connected To Instance.

Virtuoso Schematic Composer User Guide

Editing Objects

The following diagram illustrates stretching an instance named I1.

I1

(a)

(b)

When you set Reroute Wire Segments Connected To Instance to off, the rubberband lines begin at the wire (a).

When you set Reroute Wire Segments Connected To Instance to on, the rubberband lines begin at the pin (b).