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This directory contains combined SkyWater s8 (original) and sky130 (continuous)
models, released as open source by SkyWater.

The original devices models were characterized at specific device width and
length, and are considered "micro-binned";  that is, device models are
accurate for devices with width and length equal to the devices that were
characterized, and can diverge considerably for other device sizes.  The
"continuous" models have been recharacterized to ensure that parameters
are continuous across device width and length.

Not all devices in the process are includes in the continuous models.  In
particular, certain devices such as the RF transistors have fixed device
layouts and use of device sizes other than those modeled is discouraged.

The contents of this directory replace the models from the original
skywater-pdk repository under sky130_fd_pr/models/ (../models/).  This
leaves a number of "orphaned" model files (namely files ending with
".pm3.spice") in sky130_fd_pr/cells/ that are not included from any other
file.
