Virtuoso Schematic Composer User Guide

Creating Schematics

Edit Object Properties

3.In the Show field, turn on thesystem button.

4.Turn on the FreezePinCreate button.

5.Click OK.

Adding Pins

This section describes the following procedures:

■Adding Schematic and Offsheet Pins on page 152

■Showing Pin Connections on page 153

Pins represent the schematic input, output, and inputOutput terminals to which a net connects in a schematic.

Virtuoso Schematic Composer User Guide

Creating Schematics

You add pins to establish connectivity between different levels of hierarchy and to connect different sheets of a multisheet schematic.

Offsheet pin

N6

Pin name

NAND3

Schematic pin

Hierarchical pins (schematic pins) connect signals that span different levels of a hierarchical design. Offsheet pins (offsheet connectors) connect signals that span multisheet schematics.

Cadence has a large set of pin definitions in the cell category PINS of thebasic reference library. These are the pins that the system uses when you choose Add – Pin.

The following pins are examples of pins in the basic reference library.

Do not use the Add – Instance command to place these pins.

Adding Schematic and Offsheet Pins

To add a schematic pin or an offsheet pin, do the following:

1. Choose Add – Pin.

Virtuoso Schematic Composer User Guide

Creating Schematics

The Add Pin form appears.

2.In the Pin Names field, type a pin name or multiple pin names separated by spaces.

Use the same naming conventions for pins as for wires. Use a vector expression to name bus pins.

3.Set the Usage cyclic field toschematic for a schematic pin or offsheet to connect the pin to another sheet in a multisheet schematic.

4.Move the pointer into the schematic and click. The pin name appears next to the pin.

Showing Pin Connections

To enable the display option for highlighting the connection between pins, do the following:

1.Choose Options – Display.

The Display Options form appears.

2.Turn the Show Direct Connections option on.