Why to use Allegro System Capture – Importing and Instantiating a Hierarchical Block

A hierarchical design is recommended for creating complex designs that can be organized into modules. This method is useful when the same circuit needs to be reused.

In a hierarchical design, block symbols are created for each of the blocks representing the underlying circuitry. Each block symbol contains pins that are the interfaces to the block. These block symbols can be instantiated and interconnected to simplify complex designs.

System Capture supports complex hierarchy and does not have any limitation on the number of hierarchical levels. All the connectivity and constraints captured in the block are reused in the design. When working with hierarchical designs, the following tasks are commonly performed:

1. Importing and Instantiating a Block
2. Viewing and Editing a Block
3. Adding Multiple Levels of Hierarchy
4. Resolving Interface Connectivity Changes
5. Creating a New Block

Importing and Instantiating a Block

System Capture can import designs/blocks created in DE-HDL or System Capture. In case of multi-level hierarchy, all the blocks are imported along with the main block. To import a block:

• Choose File > Import > Block(s).

• Browse to the project file and select the block to import.

After the block is imported, it is displayed in the Project viewer.

To instantiate the imported block, right-click the block in the Project viewer and choose Place > Schematic Block from the pop-up menu. The block is attached to the mouse pointer. Place the block on the schematic canvas and choose the appropriate packaging option.

Team DesignTech
Cadence Design Systems