Austin Rovinski comments

Results 61 comments of


Austin Rovinski

cell_footprint value in liberty files doesn't match name in verilog or GDS.

The only place where `cell_footprint` really shows up is vt-swapping. The property is used to identify if different cells have the same geometric footprint so that they can be swapped...

cell_footprint value in liberty files doesn't match name in verilog or GDS.

@msaligane Do you mean different drive strengths or different VTs? Cells with different drive strengths often have different footprints.

cell_footprint value in liberty files doesn't match name in verilog or GDS.

@RTimothyEdwards I could be wrong here, but I've only seen footprint to mean "LEF abstracts are identical", i.e. pins, obstructions, and dimensions are all identical. This is to allow swapping...

cell_footprint value in liberty files doesn't match name in verilog or GDS.

Actually I took a quick survey of commercial PDKs I have access to. Some adhere to my definition, some adhere to @RTimothyEdwards's definition. I found [this post](https://www.edaboard.com/threads/reg-cell-footprint-in-vlsi.244029) which seems to...

cell_footprint value in liberty files doesn't match name in verilog or GDS.

I feel like the doc is conflicting. Under 1.6.11: > The `in_place_swap_mode` attribute specifies the criteria for cell swapping during in-place optimization. The basic criteria for cell swapping are: >...

cell_footprint value in liberty files doesn't match name in verilog or GDS.

> If two cells have different `cell_footprint` values **even** if their footprint otherwise matches they can **not** be swapped. > > Said another way, if you have two and4 gates...

Import capacitance data from Google Spreadsheet into the PDK

> What is the data format needed by the open source tools? To my knowledge there aren't really any open source extractors currently available. [OpenRCX](https://github.com/The-OpenROAD-Project/OpenRCX) is in the works, but...

Import capacitance data from Google Spreadsheet into the PDK

@20Mhz usually in ITFs there's a lot of information dedicated to variation caused by etching and thickness. So I expect to see tables like `ETCH_VS_WIDTH_AND_SPACING`, `RHO_VS_WIDTH_AND_SPACING`, and `POLYNOMIAL_BASED_THICKNESS_VARIATION`. I suppose...

Import capacitance data from Google Spreadsheet into the PDK

Those sheets include temperature variation (`C1` & `C2`), but they don't look like they have any process variation. The metal layer sheet has `StdDev` as "0" for every layer, and...

Import capacitance data from Google Spreadsheet into the PDK

That looks like an ICT file (compatible with Cadence tools). It provides some more information, like `wire_edge_enlargement`. But `wire_edge_enlargement` usually has an array of values for `wee_widths`, `wee_spacings`, and `wee_adjustments`....