Question 3: how can I know the purpose of each cell of sky130_fd_sc_hd ?

One would think there would be a list somewhere, but if so I do not know where it is located. The libraries are located in

<https://github.com/google/skywater-pdk>

. Each cell has a file "definition.json" in the tree, such as the one located

here

. I think each file has a line such as this one.

"description": "2-input AND into first input of 4-input OR.",

You could clone the repo and then write a simple bash for loop to echo the cell and grep for description in each file.

Thanks David 🙏

In case you haven't found this, here's an overview of each library. https://skywater-pdk.readthedocs.io/en/main/contents/libraries/foundry-provided.html