Best strategy for adding dummies for CC placement

Dear Supriyo,

supriyo1985 said:

Is it possible to introduce dummy components exclusively to the layout without altering the schematic?

In my experience, we always included "dummy elements" placed in the layout (i.e., those used to promote matching or minimize layout effects in general) in the schematic to allow for a successful LVS. I am not aware of a means to validate the connectivity and topology of a layout with a corresponding schematic without including all devices contained in the layout in the schematic.

Shawn

Dear Supriyo,

supriyo1985 said:

Is it possible to introduce dummy components exclusively to the layout without altering the schematic?

In my experience, we always included "dummy elements" placed in the layout (i.e., those used to promote matching or minimize layout effects in general) in the schematic to allow for a successful LVS. I am not aware of a means to validate the connectivity and topology of a layout with a corresponding schematic without including all devices contained in the layout in the schematic.

Shawn

There are essentially two flow options here...

1) Add the dummies to the schematic. LVS will check and match accordingly. N.B. Virtuoso includes functionality to automatically generate and backannotate the dummies to the schematic.

2) Do not Add dummies to the schematic. The LVS rules/options must be set to filter such devices. e.g. Filter devices with all terminals shorted (see rules commands for your selected lvs tool).

Rob.

This is what I have done. I have added 16 dummies to maintain the common centroid layout structure while sharing the diffusion region. I did not change the schematic. For the time being, this is what I need. Thanks for the input.