在实际Layout过程中，差分对上往往串接有电阻，电容或共模电感。这时候就需要创建Xnet。那么Allegro如何创建Xnet呢？

1、点击菜单 Analyze（分析）→Model Assigment（模型分配），如下图所示

2、跳出SI Design Audit对话框，直接点OK，如下图所示

3、接着跳出下面的对话框，也不用管，点是

4、然后跳出下面对话框（Signal Model AssIgnment），如下图所示

5、不要关闭此窗口，此时选中需要取消的差分对内串接的阻容器件。

然后点击需要取消Xnet的器件。如下图所示

然后Model选择：No Model。

然后点击OK，即可。

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Allegro provides a good and interactive working interface and powerful functions, and its front-end products Cadence, OrCAD, Capture, the combination of high-speed, high-density, multi-layer complex PCB design routing provides the most perfect solution.

Allegro has perfect Constraint Settings, users only need to set the wiring rules according to the requirements, and the design requirements of the wiring can be achieved without violating the DRC when routing, thus saving the tedious manual inspection time and improving the work efficiency!

It can also define parameters such as minimum wire-width or wire-length to meet the needs of today's high-speed circuit board wiring.

Constraint Manger provides a simple interface for users to set and view Constraint declarations.

Its combination with Capture allows E.E. electronics engineers to set up regular data when drawing a circuit diagram and bring it with them to the Allegro working environment, where it can be automatically processed and checked when placing parts and wiring. The empirical values of these regular data can be reused for the same nature of the circuit board design.

In addition to the above functions, Allegro's powerful automatic push and stick line and perfect automatic repair line function provide users with great convenience;

The powerful mapping function can provide multiple users to deal with a complex board at the same time, thus greatly improving the work efficiency.

Or use the optional graph cutting function to cut the circuit board into various blocks, so that each block has a full-time person at the same time to design, to achieve the purpose of the same graph design and can shorten the time course.

After renaming, online interchange and modifying logic during routing, users can easily return to Capture wiring diagram, and update the wiring diagram to Allegro after modification.

Users can also click and modify objects between Capture and Allegro.