Virtuoso XL Layout Editor User Guide

Wire Editing in the Virtuoso XL Layout Editor

About the Forms

Add Via Form

Displays vias and routing layers that have been defined in the rules file or technology file. You can either choose the layer you want to change to or choose a via type on the layer.

The Add Via form consists of a matrix of layer and via buttons in rows and columns. Each row in the matrix represents a routing layer and contains a button for the layer and buttons for the vias that can reach that layer from the current layer. The first column contains the buttons for the layers. The other columns contain buttons for each available via type for the given layer. The buttons are color coded by layer color, and the layer name appears on each layer button.

Buttons for layers that can be reached from the current active layer are enabled, while buttons for inaccessible layers are grayed out.

Rotate Via rotates vias 90 degrees as you place them.

Virtuoso XL Layout Editor User Guide

Wire Editing in the Virtuoso XL Layout Editor

Check Routes Form

Rules

Conflict checks for shorts and clearance violations.

Crosstalk checks for crosstalk rule violations. To control crosstalk, limit the lengths of parallel wire segments for a given wire-to-wire gap. The parallel_segment crosstalk rule limits the distance that wire segments on the same layer can be parallel, and the tandem_segment crosstalk rule limits the distance that wire segments on adjacent layers can be parallel.

Limit Way checks for limit_way rule violations. The limit_way rule defines the maximum wrong-way distance permitted in a connection. The wrong way direction is vertical on horizontal routing layers and horizontal on vertical routing layers.

Maximum Process Wire Width checks for maximum process width rule violations.

Minimum Mask Edge Length checks for the minimum dimension for any edge of a shape at the mask level.

Miter checks for unmitered corners.

Polygon Wire checks for clearance violations from polygon wire shapes to pins, fixed wires, protected wires, and fixed or protected vias.

Re-Entrant Path checks for wire loops that have been created while routing or editing.

Segment checks for maximum segment rule violations. The max_segment rule controls the total routed length on a layer.

Use Layer checks for use_layer rule violations. The use_layer rule assigns one or more routing layers to a net, class, group, group set, or fromto.

Wire Extension checks for path extension violations. Path extension rules define the amount of routing path material needed beyond the path end at a via.

Corner - Corner checks for a larger corner-to-corner clearance, rather than an edge- to-edge clearance between shapes. Corner-to-corner clearance is the minimum corner- to-corner clearance between two shapes and can vary from the edge-to-edge clearance to a maximum value of 1.414× (edge-to-edge clearance value) at 45 degrees.

Length checks for length_rule violations.

Maximum Stacked Via Depth checks for stack_via_depth violations. stack_via_depth limits how many vias can be stacked at one location.

Minimum Process Wire Width checks for minimum process width rule violations.

Virtuoso XL Layout Editor User Guide

Wire Editing in the Virtuoso XL Layout Editor

Maximum Total Via checks for the max_total_vias rule, which controls the maximum number of vias permitted on a net.

Net Order checks routed wiring for violations of the net ordering rules. The net ordering choices are, Starburst, Daisy, Mid-Driven Daisy, Balanced Daisy.

Protected checks for clearance violations between protected wires or vias and other protected or fixed objects.

Same Net checks for same-net violations such as notches, gaps, and loops.

Stub checks for maximum stub length rule violations. Stub length is the distance between a pin or via and a tjunction. Stub length is measured from the edge of a via or pin to the center of the tjunction.

Use Via checks for use_via rule violations. You can control which via is used to route a group, net, or class of nets by setting a use_via rule.

Pin Data

Pin Spacing checks the edge-to-edge spacing between pins.

Off Manufacturing Grid Pin checks for pins that are located off the manufacturing grid.

Off Wire Grid Pin checks for pins that are not centered on a wire grid.

Pin Larger Than Maximum Process Width checks for pins that are larger than the maximum process width rule. Both dimensions of rectangular pins are check.

Pin Smaller Than Minimum Process Width checks for pins that are smaller than the minimum process width rule. Both dimensions of rectangular pins are checked. Nonrectangular pins are not checked.

Inaccessible Pin checks for pins that are blocked by a keepout, boundary, or other obstructions.

Virtuoso XL Layout Editor User Guide

Wire Editing in the Virtuoso XL Layout Editor

Create Path Form

Width lets you enter a value for the width of the current path.

Note: Setting a width value or applying a width change to a path does not alter the width rule for the path.

Match Pin Width sets the net width to the width of the pin you are editing.

Narrow sets the width of the active segment to match the shortest side of the pin to which the path is attached.

Wide sets the width of the active path segment to match the longest side of the pin to which the path is attached.

Match Path Width sets the net width to the width of the net you are editing.

Snap Mode limits how the cursor snaps when you create the path. anyAngle creates paths at any angle.

diagonal creates paths parallel to the X or Y axis or at a 45-degree angle to the axes. orthogonal creates paths parallel to the X or Y axis.

L90XFirst creates orthogonal two-segment paths and creates the first line in the X direction.

L90YFirst creates orthogonal two-segment paths and creates the first line in the Y direction.

Net Name assigns a net name to floating paths.