Allegro PCB Design Tutorial

Placement Reuse in Allegro PCB Design

It often happens that your design has a set of two or more symmetrical components. The relative position of the components in placemnt is symmetrical. So there should be some way of reusing the effort for other group of componets. Allegro provides this facility using Placement reuse with the concept of modules.

We will learn it with example, as this is the best way to understand tge concept. Take a look at an overly simplified schematics. We have kept the schematics deliberately simple, so that we can focus on learning. The same trick can then, be applied to more complext circuit.

The circuit is very simple. It has two symmetrical group each having two comnnectors. The firs group has J33 and J43 and the second group has J42 and J31. In real layout these two groups will have identical placements. So we place one group as perfectly as possisble as then replicate the things to to second group.

To start creating a resue module, first go to Setup -> Application Mode and select Placement Edit. We assume that you have aleady placed the 4 components in an unorderly but two visibly separate group. Like something like this.

Now place the first set ( J33 and J43) manually - as best as you can. It is here you should pay attention as much as possible ( real world circuit may have 10s of components - that will take time).

Now select J33 and J43 and right click and click "place replicate create". It will ask for a file name. Give a suggestive file name. Now select the group of components you would like to apply this (In our case it is J31 and J42). Then right click and click on Place replicate apply and select the file name that you created earlier ( e.g. USB).

This will make the second group look like the first group.
We have created youtube for it.