Stdcell schematics reference

[aviadb]

Hello,
I see that xschem symbols are provided with the basic set of standard cells, however couldn't see the schematics themselves in the repo.
May I ask for the schematics for a reference please?
If exporting the schematics in xschem format is not an option, would it be possible to share the reference schematics as a snapshot or in a pdf file instead?

The reference schematics will be used for contributions to the stdcell lib.

Thanks

[sergeiandreyev]

Hi @aviadb, unfortunately, we cannot provide even screenshots of schematics from proprietary PDK.. the only way is to use CDL/SPICE netlists to restore the stdcell schematic, but it will be of course quite cumbersome (btw, this is how it was done for IO cells: #171)

[aviadb]

Thank you for your reply @sergeiandreyev .
I've seen a related comment in this thread #152

I have not seen XSchem schematics for the IHP standard cells in this repository

We will provide some sample xschem schematic views for combinational and sequential cells to take as an example for the open source community contributions

Originally posted by @sergeiandreyev in #152 (comment)

Any update on this?

[sergeiandreyev]

this one is still not done yet, because we reprioritized this task in favor of providing IO cells schematics in xschem - and even with that the data is not yet merged to the dev branch
thanks for reminder on the stdcell schematics, I'll try to prioritize the task (inverter can do on my own ;)

[sergeiandreyev]

Hi @aviadb, we have an example of inv_1 cell schematic now in the dev branch:
79e465a

[aviadb]

Thanks @sergeiandreyev .
I am more interested in the DFF cells for my trials to create synchronization cells and adding scan chains.
Looking forward for those cells to be added.

[sergeiandreyev]

Hi @aviadb, please take a look at sdfrbp_2 cell schematic. It's now available in dev branch: 3f954fa

[aviadb]

Thank you

[nmendezst]

This might be old news, but there is this cool script make_sch_from_spice.awk that generates the components, pins and nodes from the spice netlist. With a couple of changes works just fine with the IHP SG13G2 PDK.

Another one that looks very promising, it's capable of auto-grouping spice2sch, although at the moment works only for SKY130 and only supports transistors.