-
- EraseBehindTerms
Value: boolean or ``all''.
If set, the area inside the bounding box of terminals made visible
by the Show Terminals command is erased, to promote visibility
of the text. If set to ``all'', all terminals are erased
behind, otherwise only the cell's formal terminals are erased behind.
This tracks the setting of the Erase behind physical terminals
menu in the Misc. Extraction Settings panel from the Misc
Config button in the Extract Menu.
- TermTextSize
Value: integer 6-48.
This variable can be used to set the height, in pixels, of the text
used in rendering terminals and cell labels in electrical mode. If
not set, the default is 14.
This tracks the setting of the Terminal text pixel size
entry in the Misc. Extraction Settings panel from the Misc
Config button in the Extract Menu.
- TermMarkSize
Value: integer 6-48.
This variable can be used to reset the pixel size of the cross used as
a terminal mark. If not set, the default is 10.
This tracks the setting of the Terminal mark size entry in the
Misc. Extraction Settings panel from the Misc Config
button in the Extract Menu.
- ExtractOpaque
Value: boolean.
When set, Xic will ignore the OPAQUE flag and perform
extraction normally on cells with this flag set. The OPAQUE
flag would otherwise suppress extraction on the contents of the cell.
This flag is set in the Flags property of physical cells.
This tracks the setting of the Extract opaque cells, ignore
OPAQUE flag check box in the Misc. Extraction Settings panel
from the Misc Config button in the Extract Menu.
- FlattenPrefix
Value: string.
This variable can be set to a string containing a space-separated list
of words. The words are intended to match cell names or classes of
cell names. Cells with names that match are not treated as
individual cells extraction, instead they are treated as if
instantiations are part of the containing cell, i.e., they are
logically flattened. This applies to physical cells only, and such
cells will have no recognized electrical counterpart.
Note: it is probably more convenient to set the Flatten
property of physical cells that should be flattened into their parent
during extraction. Setting this property with the Cell Property
Editor will have the same effect as including the cell in the
FlattenPrefix list, but is persistent when the cell is saved.
In the words, the forward slash character (`/') is special, and is
used to indicate the type of matching. A word in the form ``name[/]'', where the trailing slash is optional, indicates prefix
matching. Cell names whose leading characters match name will
match. A word in the form ``/name'' indicates suffix
matching, where if the trailing characters of a cell name match name, a match is indicated. Finally, a word in the form ``/name/'' implies a literal match. Only the cell name given in name will match.
This tracks the setting of the Cell flattening name keys entry
in the Device Extraction Settings panel, which is obtained from
the Settings button in the Show/Select Devices panel from
the Device Selections button in the Extract Menu.
Note: in Xic releases prior to 3.1.8, this variable could be set
to a single word only, and prefix matching was always employed. In
releases of Xic prior to 2.5.19, this variable was named
``PnetFlattenPrefix''.
- GroundPlaneGlobal
Value: boolean.
When set, every object in every cell on a clear-field ground plane
layer is assigned to group 0. If not set, only the largest area group
on this layer, in the top-level cell, is assigned to group 0.
This tracks the setting of the Assum clear-field ground plane is
global check box in the Misc. Extraction Settings panel from
the Misc Config button in the Extract Menu.
- GroundPlaneMulti
Value: boolean.
When set, a layer specified as GroundPlaneClear in the
technology file will be inverted, and the inverted version used for
grouping and extraction. The MultiNet keyword which optionally
follows GroundPlaneClear in the technology file effectively sets
this variable. If this variable is unset, then no inversion takes
place, and the absence of the GroundPlaneClear layer is taken to
indicate ground (group 0). This variable has no effect unless a GroundPlaneClear layer exists.
Note: This replaces the HandleTermDefault variable
which existed in earlier Xic releases.
This tracks the setting of the Invert dark-field ground plane for
multi-nets check box in the Misc. Extraction Settings panel
from the Misc Config button in the Extract Menu.
- GroundPlaneMethod
Value: integer 0-2.
This sets the method used to invert the ground plane for grouping and
extraction, if the MultiNet keyword has been applied to a GroundPlaneClear layer in the technology file. The possible values
are integers 0-2, which have the same meaning as the integer that
optionally follows MultiNet in the technology file (see
13.1.2).
This tracks the setting of the inversion method menu in the Misc.
Extraction Settings panel from the Misc Config button in the
Extract Menu.
- KeepShortedDevs
Value: boolean.
By default, if an extracted device is found to have all terminals
shorted together at the time the device is recognized, the device will
be ignored. This will help reject spurious devices from test
structures, etc.
If the KeepShortedDevs variable is set, then these devices will
be kept (as in pre-2.5.69 releases). This flag may be needed for LVS
to pass, if the schematic contains the shorted devices.
This tracks the setting of the Keep devices with terminals
shorted check box in the Device Extraction Settings panel,
which is obtained from the Settings button in the Show/Select Devices panel from the Device Selections button in
the Extract Menu.
- LvsFailNoConnect
Value: boolean.
During LVS analysis, the electrical (schematic) part of the design is
used as the basis for recursion through the hierarchy. Thus, physical
subcells that have no connection to the circuit will not be detected,
and are basically ignored. However, an explicit test is performed for
such cells, and those found will be listed in the LVS report. If this
variable is set, the presence of such cells will force LVS failure,
otherwise they are ignored for comparison purposes.
This variable tracks the state of the fail if unconnected
physical subcells check box in the panel brought up by the Dump
LVS button in the Extract Menu.
- NoPermute
Value: boolean.
When this variable is set, the association algorithm will not attempt
to iterate through the combinations when searching for a solution.
Many circuits do not require a permutation search, however some
circuits, and in particular circuits where the wiring is incomplete,
may require a lot of time for the permutation search. Of course, if a
permutation search is needed and not performed, LVS will fail. This
variable is mostly for debugging, or for cases where association is
not needed.
Permutes are also skipped if a device or subcircuit is found that can
not possibly be associated.
This tracks the setting of the Skip device terminal permutations
in association check box in the Misc. Extraction Settings
panel from the Misc Config button in the Extract Menu.
- NoMergeParallel
Value: boolean.
Setting this variable suppresses merging of parallel-connected devices
during extraction. This applies to all devices, and supersedes the
Merge directive in the device blocks or the technology file.
This tracks the setting of the Don't merge parallel devices check
box in the Device Extraction Settings panel, which is obtained
from the Settings button in the Show/Select Devices panel
from the Device Selections button in the Extract Menu.
- NoMergeSeries
Value: boolean.
Setting this variable suppresses merging of series-connected devices
during extraction. This applies to all devices, and supersedes the
Merge directive in the device blocks of the technology file.
This tracks the setting of the Don't merge series devices check
box in the Device Extraction Settings panel, which is obtained
from the Settings button in the Show/Select Devices panel
from the Device Selections button in the Extract Menu.
- NoMeasure
Value: boolean.
This turns off the extraction of parametric data for devices in the
extraction system. This is mainly for debugging, but may save time if
the user is interested in topology only. The measurements can be time
consuming.
This tracks the setting of the Skip device parameter measurement
check box in the Misc. Extraction Settings panel from the Misc Config button in the Extract Menu.
- QpathGroundPlane
Value: integer 0-2.
This variable controls how the "Quick" Path command in the
extraction Path Selection Control panel uses the inverted ground
plane. Normally, during extraction, if the GroundPlaneClear
keyword has been given, an inverted ground plane is created on a
temporary layer for internal use. Since the "Quick" Path mode
operates outside of the extraction system, the inverted ground plane
may or may not be available. The choices are:
- 0
Use the inverted ground plane if available. This is the default. If
an inverted ground plane has already been created and is current, it
will be used when determining paths. If the ground plane does not
have a current inversion, the absence of the layer will imply a ground
contact, as in extraction without the MultiNet keyword. This
choice avoids the sometimes lengthly inversion computation, but makes
use of the inversion if it has already been done.
- 1
Create the inverted ground plane if necessary, and use it. If the
extraction system would use an inverted ground plane, it will be
created if not already present and current. The path selection
will include the inverted layer.
- 2
The "Quick" Path mode will never use the inverted ground
plane.
This variable tracks the state of the "Quick" Path ground plane
handling menu in the Path Selection Control panel.
- NoEnet
Value: boolean.
If set, the netlist is skipped when writing output in the Dump
Elec Netlist command. This variable corresponds to the net
check box available in that command, with inverse logic.
- EnetSpice
Value: boolean.
If set, SPICE output is included in the file produced from the Dump Elec Netlist command. This variable corresponds to the spice check box available in that command.
- EnetBottomUp
Value: boolean.
When set, the electrical netlist file (produced by the Dump Elec
Netlist command) order will be leaf-to-root, i.e., subcells will be
listed first. If not set, the reverse order is used.
- NoPnet
Value: boolean.
If set, the extracted netlist listing is skipped in output from the
Dump Phys Netlist command. This variable corresponds to the
net check box available in that command, with inverse logic.
- NoPnetDevs
Value: boolean.
If set, the extracted device listing is skipped in output from the
Dump Phys Netlist command. This variable corresponds to the
devs check box available in that command, with inverse logic.
- NoPnetSpice
Value: boolean.
If set, the SPICE listing of extracted devices is skipped in output
from the Dump Phys Netlist command. This variable corresponds
to the spice check box available in that command, with inverse
logic.
- PnetBottomUp
Value: boolean.
When set, the physical netlist file (produced by the Dump Phys
Netlist command) order will be leaf-to-root, i.e., subcells will be
listed first. If not set, the reverse order is used.
- PnetShowGeometry
Value: boolean.
If set, the net field (if activated) in the file produced from
the Dump Phys Netlist command will include a listing of the
objects that comprise the wire net. The listing is in modified CIF
syntax where 1000 units per micron is used. This variable corresponds
to the show geometry check box available in that command.
- PnetIncludeWireCap
Value: boolean.
If set, the spice field (if activated) in the file produced from
the Dump Phys Netlist command will include capacitors
representing the computed wire net capacitance to ground. The Routing layers must have the Capacitance keyword applied in the
technology file. The added capacitors have a special prefix ``C@NET'' which allows them to be subsequently recognized as wire net
capacitors by Xic. This variable corresponds to the include
wire cap check box available in that command.
- PnetListAll
Value: boolean.
In files produced with the Dump Phys Netlist command, references
to subcells that are flattened or wire-only are normally not listed.
If this variable is set, these cells are included in the listing,
which may be useful for debugging. This variable corresponds to the
include all devs check box available in that command.
- PnetNoLabels
Value: boolean.
From some tools, cell terminals may be indicated by the presence of a
label on a ROUTING layer, positioned such that the label reference
point touches an object on the same layer. Such labels, if found,
will be used to generate a terminal list for the top-level cell in the
extracted hierarchy, if the existing electrical cell contains no
terminals (or the electrical cell doesn't exist). If this variable is
set, these labels will be ignored by default when generating a netlist
from a physical layout.
- SourceAllDevs
Value: boolean.
In the Source SPICE command, ordinarily only devices which have
fixed (user-specified) device names will have properties updated.
This is to avoid errors, since the internally generated names can
change, and may not match those in the SPICE file. If this variable
is set, the default action is to update all devices. This variable
corresponds to the all devs check box available in that command.
- SourceCreate
Value: boolean.
In the Source SPICE command, if this variable is set, the
default action is to create missing devices. Otherwise, device
parameters may be updated, but no new devices are created. This
variable corresponds to the create check box available in that
command.
- SourceClear
Value: boolean.
In the Source SPICE command, if this variable is set the default
action is to discard the existing contents of the electrical part of
the cell before updating. This variable corresponds to the clear check box available in that command.
- SourceGndDevName
Value: string.
This variable specifies the name of the ground terminal device to use
when devices are created and placed in the Source SPICE and
(consequently) the Source Physical extraction commands. If not
set, the name ``gnd'' will be assumed. If this variable is set
to a name, a ground device of that name must appear in the device
library file.
- SourceTermDevName
Value: string.
This variable specifies the name of the terminal device to use when
devices are created and placed in the Source SPICE and
(consequently) the Source Physical extraction commands. If not
set, the name ``tbar'' will be assumed, if that name is found
for a terminal device in the device library. If not found, the name
``vcc'' will be assumed. If this variable is set to a name,
that name must match the name of a terminal device in the device
library file.
- NoExsetAllDevs
Value: boolean.
In the Source Physical command, if this variable is set, only
devices that have a permanent (user-supplied) name will be updated.
If not set, all devices will be updated. This variable corresponds to
the all devs check box available in that command, with inverse
logic.
- NoExsetCreate
Value: boolean.
The default behavior of the Source Physical command is to create
missing devices. Setting this variable will change the default action
to no device creation. This variable corresponds to the create
check box available in that command, with inverse logic.
- ExsetClear
Value: boolean.
When set, the electrical cells are cleared before updating with the
Source Physical command. This implies create, i.e., new
devices will be created since the cell is empty. This variable
corresponds to the clear check box available in that command.
- ExsetIncludeWireCap
Value: boolean.
When set, computed routing capacitors will be updated or created in
the electrical database when using the Source Physical command.
These capacitors have a name prefix of ``C@NET''. This variable
corresponds to the include wire cap check box available in that
command.
- ExsetNoLabels
Value: boolean.
From some tools, cell terminals may be indicated by the presence of a
label on a ROUTING layer, positioned such that the label reference
point touches an object on the same layer. Such labels, if found,
will be used to generate a terminal list for the top-level cell in the
extracted hierarchy, if the existing electrical cell contains no
terminals (or the electrical cell doesn't exist). If this variable is
set, these labels will be ignored by default when extracting
electrical data from physical layouts.
- PathFileVias
Value: boolean or string.
This variable determines whether and how vias are included in the
files produced with the Save path to file button in the Path Selection Control panel from the Net Selections button in
the Extract Menu. It tracks (and sets) the state of the Path file contains vias and Path file contains check layers
check boxes in the panel.
If not set, via layers will not be included in the file, only the
conductors will appear. If set as a boolean (i.e., to no value), the
via layers will be included, but not the check layers. If set to any
text, the check layers will also be included.
- RLSolverDelta
Value: floating point > = 0.01.
It this value is set, the resistance/inductance extractor will assume
this grid spacing, in microns. The number of grid cells enclosed in
the device will increase for physically larger devices, so that larger
devices will take longer to extract. If this variable is set, the
other RLSolver variables are ignored. Setting this variable may
be appropriate if all resistors are ``small'' and dimensions conform
to a layout grid.
This tracks the setting of the Set/use fixed grid size entry in
the Device Extraction Settings panel, which is obtained from the
Settings button in the Show/Select Devices panel from the
Device Selections button in the Extract Menu.
- RLSolverTryTile
Value: boolean.
If set, the extractor will attempt to use a grid that will fall on
every edge of the device body and contacts. The device and contact
areas must be Manhattan for this to work. If such a grid can be
found, and the number of grid cells is a reasonable number, this will
give the most accurate result.
This tracks the setting of the Try to tile check box in the Device Extraction Settings panel, which is obtained from the Settings button in the Show/Select Devices panel from the Device Selections button in the Extract Menu.
- RLSolverGridPoints
Value: integer 10-100000.
When not tiling (RLSolverTryTile is not set), this sets the
number of grid points used for resistance/inductance extraction. This
number will be the same for all device structures, so that computation
time per device is nearly constant. Higher numbers give better
accuracy but take longer. The value used if not set is 1000.
This tracks the setting of the Set fixed per-device grid cell
count entry in the Device Extraction Settings panel, which
is obtained from the Settings button in the Show/Select
Devices panel from the Device Selections button in the Extract Menu.
- RLSolverMaxPoints
Value: integer 1000-100000.
When tiling (RLSolverTryTile is set), the maximum number of grid
cells is limited to this value. If the tile is too small, it will be
increased in size to keep the count below this value, in which case
the tiling will not have succeeded so there may be a small loss of
accuracy. Using a large number of grid points can take a long time.
The value used if not set is 50,000.
This tracks the setting of the Maximum tile count per device
entry in the Device Extraction Settings panel, which is
obtained from the Settings button in the Show/Select
Devices panel from the Device Selections button in the Extract Menu.