A layout engineer who studies signal integrity simulation.
In the last article, I shared some basic operations about copper skin shape. We lay copper to connect the network (pads, vias, etc.), usually GND or power network. Shape and wiring are still different. The wiring directly pulls out a layout from the pad or via, but the shape generally covers the entire network, including pad pins and the like, so this involves Several connection methods of the shape can also be said to be the connection method of the pad, especially on the in-line device, the corresponding copper pouring method must be selected. Let me introduce to you how to set the cross connection and full connection of the pad:
First: check the default connection method when laying copper
First look at the default connection method when laying copper, which is generally full connection. We choose the GND network and lay copper on the ground pin of a connector, as shown in the figure
below: You can see that the shape covers all the pins, so it is called full connection.
Step 2: Set the Dyn_Thermal_Con_Type property
Select the Edit command under the Allegro menu, click the Properties command, select pin in the Find window, and then click the pin in the design window, and the Edit Property window will pop up, as shown in the figure below: Select the Dyn_Thermal_Con_Type property in Edit Property, and then click on the
right Value, the corresponding Subclass Value setting will pop up, as shown in the figure below:
At this time, the selected pins have been added with the Dyn_Thermal_Con_Type attribute. If we don’t want it, check the box under Delete.
Step 3: Set up different connection methods
When we set the pins, we can choose to use the same connection method for all layers, or choose different connection methods for each layer. The following types are specified here, as shown in the figure below: Then we click the arrow below
Value , you will see that there are many connection methods Orthogonal (orthogonal), Diagonal (diagonal), Full_contact (full connection), 8_way (), the two most commonly used are cross connection and full connection. As shown in the figure below:
For example, if this pin wants to set the first layer to be fully connected, the third layer to be an orthogonal cross, and the fourth layer to be a diagonal cross, you can select it in the drop-down arrow behind each layer The corresponding connection methods are shown in the figure below:
The above are different connection methods for different pads, including surface mount, direct insertion and via holes, which can be set. You can try it.
Previous article: Cadence Allegro PCB Design 88 Questions Analysis (16) The link of the shape (copper skin) operation in Allegro (1) is as follows, you can click to view it: link The above information is mainly my own in
PCB design and Organized by online search
If there are any similarities or mistakes, I hope you will leave a message and correct me, thank you! ! !
