Update

Specifies how much of the design is updated and what happens to existing layout components that need to be changed or removed from the design. The tab also specifies which missing design objects are generated in the layout view.

I/O Pins

Specifies pin attributes to be applied when pins are generated in the layout.

PR Boundary

Specifies the shape and size of the PR boundary to be generated in the layout.

Hierarchy

Specifies the scope for generating virtual hierarchies in the layout.

Update

This section lets you specify how much of the design is updated and what happens to existing layout components that need to be changed or removed from the design

Update Selected Layout Components Only

Updates only the instances and pins currently selected in the layout window.

This option automatically disables the generation of new components. However, if the Update Instance Masters option is enabled and set to Creating a New, Layout XL may generate new instances to replace existing instances with incorrect masters; you have the option to switch on Chain, Fold, and Chain Folds for these new instances.

Update Nets and Instance Name Mismatches Only

Specifies that only net assignments and instance, terminal, and net names are updated. Enabling this option also automatically preserves user-defined mappings. All other options on the form are disabled except Update Selected Layout Components Only.

If any pins have got swapped due to a schematic ECO, running the Update with Update Nets and Instance Name Mismatches Only selected ensures that the original pin positions are retained in the layout. To reflect the pin swaps in the layout, run the Update with Update Nets and Instance Name Mismatches Only deselected.

Environment variable: updateNetsOnly

Update Net Signal Types

Specifies that the signal types assigned to nets in the schematic are updated in the layout view.

The signal types can be set in the schematic and are automatically transferred to the layout during Generate All From Source. However, once set, the signal type of a net can be manually updated using the Property Editor assistant. If the signal type of a net is changed in the schematic, the Update Net Signal Types option can be used to update the layout to keep the two views in sync.

Environment variable: updateNetSigType

Update Net MinV/MaxV

Specifies that the minimum and maximum voltages assigned to nets in the schematic are updated in the layout view.

Environment variable: updateNetMinMaxVoltage

Only those voltages that are manually set on the schematic net are updated in the layout view. Layout versus schematic mismatches that may arise due to this selective transfer of voltages are not reported by the Check Against Source command.

Update Instance Masters by

Updates an existing instance that uses an incorrect master to use the correct master.

• Replacing the Old or Creating a New Instance: The default is Replacing the Old, which means the command removes the incorrect instance and replaces it with an instance of the correct master in the same location.

When set to Creating a New, the command puts a marker on the instance with the incorrect master and renames it name_old. It then creates a new instance with the correct master and places it below the PR boundary.

Because you are creating a new instance, you can optionally enable Chain, Fold, and Chain Folds in this mode.

Environment variable: updateWithMarkers

Delete Unmatched Pins

Deletes layout pins that are no longer present in the schematic. Redundant nets and terminals are deleted from the layout view at the same time. When switched off, unmatched pins are not deleted but are instead indicated with a marker in the layout view.

Environment variable: deleteUnmatchedPins

Delete Unmatched Instances

Deletes layout instances that are no longer present in the schematic. When switched off, unmatched instances are not deleted but are instead indicated with a marker in the layout view.

Environment variable: deleteUnmatchedInsts

Update Layout Parameters

Updates the parameters and parameter values automatically on layout instances to match those on their schematic counterparts. Parameters that are set in layout instances but are not present on their schematic counterparts are not removed.

Environment variable: updateLayoutParameters

Move Changed Overlapping Instances Below PR Boundary

Places instances automatically below the PR boundary if they overlap other instances during the update. The overlapping instances are the ones that have changed in size, and if placed at their original location, may overlap other unchanged instances.This data is then used by the Virtuoso Custom Digital Placer (VCP) for Eco Mode placement.

Environment variable: updatePlaceBelowBoundary

Generate

This section lets you specify which missing design objects are generated in the layout view.

Instances

Generates instances that are in the schematic but are not currently in the layout.

Chain

Automatically abuts transistors into chains during layout generation.

Fold

Automatically divides devices into folds to prevent the gate width from exceeding a specified size.

Environment variable: initDoFolding

If the disableFolding environment variable is set and the folding threshold for the component type is set to 0, folding is disabled.

Chain Folds

Chains the individual folds of a transistor automatically.

Environment variable: initDoStacking

For the Chain Folds option to be available, only the Fold check box must be selected. If you select the Chain check box as well, Chain Folds is deactivated.

I/O Pins

Generates all the pins listed on the I/O Pins tab. The generated pins are automatically snapped to the placement grid.

Environment variable: initCreatePins

Except Global Pins

Stops Layout XL generating layout pins for the global nets in the schematic.

Except Pad Pins

Stops Layout XL from generating layout pins for schematic pins that are connected to I/O pads (cells of type pad, padSpacer, or padAreaIO). When unchecked, the software generates both pads and pins.

Environment variable: initCreatePadPins

PR Boundary

Regenerates the new PR boundary based on the settings on the PR Boundary tab. All placements and estimations are based on the generated PR boundary. When switched off, the existing boundary is retained.

Snap Boundary

Generates a rectangular snap boundary that encloses the generated PR boundary. You can generate a snap boundary only if the PR Boundary option is switched on.

Environment variable: initCreateSnapBoundary

Device Correspondence

• Preserve User Defined Bindings: Preserves user-defined bindings of devices between the schematic and the layout. This option preserves only user-defined one-to-one, many-to-many, many-to-one, and one-to-many device bindings defined in the Define Device Correspondence form. It does not report missing devices or shapes within a bound group.

Environment variable: initCreateMTM

Default Values For Electrical Pins

This section lets you specify attribute values and Apply them to all the pins shown in the list box. Click Apply to apply the Layer, Width, Height, Num, and Create settings for all the listed pins.

Layer

Specifies the layer on which the pin is generated. The cyclic field lists only the conducting layers.

You can use the initIOPinLayer environment variable to specify the layer-purpose pair to use for generating the pins. The default is the current layer selected in the Layer Assistant, provided it is a valid layer.

See validLayers.

Else, it is the first extractable layer in the technology file that has a pin purpose. If an extractable layer with a pin purpose does not exist, the first extractable layer with a drawing purpose is selected as the default. If there are no extractable layers, the cyclic field lists all the valid layout layers.

Layers are extracted from the validLayers constraint only if they have a purpose defined. However, the purposes are not used to restrict the displayed layer-purpose pairs. To filter the purposes, use the initIOPinPurposeNames environment variable.

Width

Specifies the width for each pin. The default is the minWidth value set for the current layer in the technology file. Any change to the value is applied only if the new value is greater than the default value.

Height

Specifies the height for each pin. The default is the minWidth value set for the current layer in the technology file. Any change to the value is applied only if the new value is greater than the default value.

Num

Specifies how many instances of this pin to generate. If you type 0, the pin is not generated.

Create

Specifies that pins are to be generated in the layout.

Specify Pins to be Generated

This section lets you select pins from the list box and update the attribute values used when those pins are generated in the layout. Click Update to update the Layer, Width, Height, Num, and Create settings for the currently selected pins.

Select

Lets you type in a complete or partial pin name to select one or more pins in the list box.

Number Of Matches

Displays the number of pin with names that match the string you typed into the Select field.

Add New Pin

Opens the Add A New Pin Form dialog, where you can specify the name of a terminal for which to generate a new pin.

This option is available when you right-click in the Specify Pins to be Generated section.

Term Name

Specifies the schematic terminal name. You cannot change this value.

Net Name

Specifies the net associated with the pin in the layout. You cannot change this value.

If terminal and net names differ in the schematic, Layout XL generates a pin with the same name as the schematic terminal and a net with the same name as the net attached to the terminal in the schematic. If there is no explicit net label in the schematic, both the pin and the net name in the layout are the same as the schematic terminal. This is the default behavior.

Layer

Specifies the layer on which the selected pins are generated. The cyclic field offers only the conducting layers. The default is the current drawing layer if it is defined as an extractable layer in the technology file. Otherwise, it is the first extractable layer found. If there are no extractable layers, the cyclic field lists all valid layout layers.

Width

Specifies the width for each selected pin. The default is the minWidth value set for the current layer in the technology file. Any change to the value is applied only if the new value is greater than the default value.

Height

Specifies the height for each selected pin. The default is the minWidth value set for the current layer in the technology file. Any change to the value is applied only if the new value is greater than the default value.

Num

Specifies how many instances of each selected pin are generated. If you type 0, the selected pin is not generated.

Create

Specifies whether or not the selected pins are to be generated in the layout.

To limit the number of pins that are displayed in the pin table, you can set generatePinsDisplayLimit to the required display limit. If the design includes more pins than the number allowed to display in the form, the additional pins are suppressed and the form is updated to mention the number of suppressed pins. You can right-click the suppressed pin notification, and choose Un-suppress to display all the pins.

Pin Label

This section lets you specify the type of label generated when you create a pin. This setting is honored by the Generate All From Source and Generate Selected From Source commands.

Create Label As

Specifies whether a pin label is created when the pin is generated. You can choose to create either a Label object or a Text Display.

Environment variable: initIOLabelType

Click the Options button to access the Set Pin Label Text Style Form, where you can set the size, font, style, justification and orientation of the label lettering, and the drawing or pin layer on which the labels are displayed.

If your pin labels are not visible in the canvas, turn on the Pin Names option in the Display Options form. For this setting to take effect, you must set the createPinLabel environment variable to t.

Shape group box

This section lets you specify whether the place and route boundary is a rectangle or a polygon

Rectangle

Specifies a rectangular place and route boundary. Use the Area Estimation group box to specify how the size of the boundary is calculated.

Origin

Specifies the coordinates of the boundary’s origin. The default is (0.0 0.0).

Polygon

Specifies a polygonal boundary. Use the Points List to specify the coordinates of each of the vertices of the polygon.

Area Estimation group box

This section lets you specify how the system calculates the shape and size of a rectangular boundary.

Area estimation comprises two parts: the first specifies the aspect ratio and utilization of the boundary; the second estimates the size of boundary required to accommodate the components to be generated.

To specify the aspect ratio and utilization, set two of the following four parameters. Choose one of the parameters from the first cyclic list and any one of the remaining valid choices from the second cyclic list.

Utilization (%)

Specifies the percentage of area within the cell boundary that you want to fill. The default is 25.

Environment variable: initUtilization

When the Chain, Fold, or Chain Folds options are switched on in the Generate tab, the Utilization value is applied only after chaining and folding is complete so that the size of the boundary is calculated accurately.

Aspect Ratio (W/H)

Specifies the width-to-height ratio of the design boundary. A value of 1 specifies a square boundary; 0.5 specifies a boundary twice as high as it is wide; and 2 specifies a boundary twice as wide as it is high. The default is 1.

Environment variable: initAspectRatio and initAspectRatioOption

Width

Specifies the width of the design boundary. The default is the size of the last boundary or 10.

Environment variable: initPrBoundaryW

Height

Specifies the height of the design boundary. The default is the size of the last boundary or 10.

Environment variable: initPrBoundaryH

Estimator

Lets you choose the type of area estimator to be used.

PR Boundary based

Calculates the area based on the sum of the areas enclosed by all the place and route boundaries of the components to be updated.

BBox based

Calculates the area based on the sum of the areas enclosed by all the bounding boxes of the components to be updated.

Register

Opens the Add Area Estimators Form, which lets you register a user-defined SKILL function to estimate the area enclosed by a PR boundary or by the area boundary of a virtual hierarchy block. The SKILL function registered for estimating the PR boundary appears in the Estimator drop-down list and can be used to estimate the area of the top-level boundary when updating a layout. The SKILL function registered for estimating the area boundary appears in the Soft Block – Area drop-down list and can be used to estimate the area of the virtual hierarchies when updating a layout.

If you specified deferred when you registered the PR boundary area estimator and are now choosing to generate virtual hierarchies with area boundaries, the PR boundary estimation is deferred until the area boundary of the virtual hierarchy is created. This allows the area estimation function to consider the virtual hierarchy area boundary sizes when calculating the PR boundary area.

Virtual Hierarchy Area Boundary

This section lets you specify how the area boundary of a virtual hierarchy is estimated. This group box is available only when you have the Layout EXL or higher license checked out.

Enclose by

Specifies the distance from the objects inside the virtual hierarchy at which the area boundary is created.

Utilization (%)

Specifies the acceptable area utilization percentage for deriving the size of the area boundary for the virtual hierarchy.

Environment variable: areaBoundaryUtilization

Top Level

Specifies that the selected area boundary settings be used for creating virtual hierarchy area boundaries only at the top level.

All Levels

Specifies that the selected area boundary settings be used for creating virtual hierarchy area boundaries at all levels within the virtual hierarchy of the top-level design.

None

Specifies that the virtual hierarchy area boundaries are not created, instead existing virtual hierarchy boundaries are used.

Soft Block

This section lets you specify the area of a soft block to be created. This group box is available only when you have the Layout EXL or higher license checked out.

Area

Specifies the area of the soft blocks to be created.LLIf a SKILL function has been registered to estimate the area of a virtual hierarchy, the function appears in the drop-down list associated with the Area field. The same area estimator function can be accessed using the Adjust Area Boundary form in the Virtuoso Design Planner.

Environment variable: softBlockArea

Scope

This section lets you specify the extent in the hierarchy to which the design is updated

All cells in design

Specifies that the selected updates are carried out to all the nontransparent cellviews in the design hierarchy. When this option is enabled, the Generate – PR Boundary option on the Update tab is disabled to prevent recreating the PR boundaries across the hierarchy.

Design Planning

This section lets you specify if the virtual hierarchy is updated to match the schematic hierarchy and if soft blocks are automatically generated for missing layouts. The group box is available only when you have the Layout EXL higher license checked out.

Virtual Hierarchy

Lets you generate a virtual hierarchy using the area boundary options selected in the PR Boundary tab, or updates an existing virtual hierarchy to match the schematic hierarchy. When updating an existing virtual hierarchy, the area boundary of the virtual hierarchy is not updated.

Environment variable: generateVirtualHierarchy

Auto Generate Soft Blocks

Lets you generate soft blocks for top-level virtual hierarchy blocks that have no schematics available or have schematics with only pins but no instances or physical binding. For the virtual hierarchy blocks that have no schematic available, soft block generation uses the bound symbol view to generate pins. Soft block boundary is generated using the options defined on the PR Boundary tab.

Environment variable: generateSoftBlocks

Update soft blocks when symbol is modified

Updates the soft block in the layout to match the schematic symbol.

Environment variable: updateSoftBlocksFromSymbol

Auto place generated instances inside existing virtual hierarchy

Places instances missing from a virtual hierarchy inside the virtual hierarchy automatically, retaining the placement of the existing instances. After placement, if the virtual hierarchy contents extend beyond the area boundary and the area boundary is rectangular, the boundary automatically adjusts to enclose the contents. Rectilinear area boundaries that have their contents extending beyond the boundary need to be manually adjusted and placed.

For the generated instances to be automatically placed inside an existing virtual hierarchy, the placement status of the virtual hierarchy should be set to None.