non-Manhattan geometry is analyzed for resistance extraction.
This patch merely prevents the crash condition. It does not
solve the root of the problem, which is that split tiles can
belong to two different nets, but the tile can hold extraction
information for at most one of those nets.
a method that failed to work on devices with complex shapes on the
device recognition layer, such as snake-geometry resistors. (2)
The use of contact type "xpc" in the sky130 tech file as its own
contact residue caused the contact tracing in extresist to fail.
I opted to keep the unorthodox contact description in the tech
file and wrote an extension to a routine in extresist to handle
the case.
this appears to work correctly but does not yet handle the implicit
substrate (space as substrate) or "virtually" isolated substrate regions
(which need to be removed for full parasitic extraction).
support of devices with terminals on different plances, such as
capacitors, diodes, and bipolar transistors. Output now appears
to give meaningful results for flattened layouts, although
numerous issues remain for hierarchical layouts.
the last commit, unfortunately. Thanks to Matt Guthaus for alerting me
to this. Also updated parts of the extresist code that remove the
dependence on ResConDCS; this is a minor update and should not affect
the operation of extresist. It is preparatory to doing more work to
support additional device types like capacitors, bipolars, and diodes.
simple FET device in extresist. Also: Extended the bloat-all CIF operator
again, allowing the trigger layer for the bloat operation to include both
CIF layers and magic layers (previously only magic layers were supported).
This extension is possible due to the previous extension allowing the
trigger layer and bloating layers to be on separate planes. This operator
extension is useful for tagging geometry that is in the proximity of, but
not overlapping, geometry on another plane.
to be more robust and not depend on the ordering of the devices in
the techfile. The extraction method now keeps a mask of which
properties of the device (source/drain types, substrate type,
identifier type) have been found, and will look only for device
records that match what is known about the device. Added a device
identifier record which is the last record before parameters if the
record begins with "+". This allows marker layers to be placed
over a device such that it will extract with a different type.
This helps reduce the complexity of the techfile and allows
certain specialized devices like RF or ESD to be identified without
a separate layer type for the device.
Tim Edwards
Sean Cross