EXT2SIM(1)                                                    General Commands Manual                                                   EXT2SIM(1)

NAME

       ext2sim - convert hierarchical ext(5) extracted-circuit files to flat sim(5) files

SYNOPSIS

       ext2sim  [  -a  aliasfile  ]  [  -l  labelsfile  ]  [  -o simfile ] [ -A ] [ -B ] [ -F ] [ -L ] [ -t ] [ extcheck-options ] [ -y num ] [ -f
       mit|lbl|su ] [ -J hier|flat ] [ -j device:sdRclass[/subRclass]/defaultSubstrate ] root

DESCRIPTION

       Ext2sim will convert an extracted circuit from the hierarchical ext(5) representation produced by Magic to the flat  sim(5)  representation
       required  by  many  simulation  tools.   The  root of the tree to be extracted is the file root.ext; it and all the files it references are
       recursively flattened.  The result is a single, flat representation of the circuit that is written to the file root.sim,  a  list  of  node
       aliases  written  to  the  file  root.al,  and  a  list of the locations of all nodenames in CIF format, suitable for plotting, to the file
       root.nodes.  The file root.sim is suitable for use with programs such as crystal(1), esim(1), or sim2spice(1).

       The following options are recognized:

       -a aliasfile
                 Instead of leaving node aliases in the file root.al, leave it in aliasfile.

       -l labelfile
                 Instead of leaving a CIF file with the locations of all node names in the file root.nodes, leave it in labelfile.

       -o outfile
                 Instead of leaving output in the file root.sim, leave it in outfile.

       -A        Don't produce the aliases file.

       -B        Don't output transistor or node attributes in the .sim file.  This option will also disable the output of information such as the
                 area  and perimeter of source and drain diffusion and the fet substrate. For compatibitlity reasons the latest version of ext2sim
                 outputs this information as node attibutes.  This option is necessary when preparing input for programs  that  don't  know  about
                 attributes, such as sim2spice(1) (which is actually made obsolete by ext2spice(1), anyway), or rsim(1).

       -F        Don't output nodes that aren't connected to fets (floating nodes).

       -L        Don't produce the label file.

       -tchar    Trim characters from node names when writing the output file.  Char should be either "#" or "!".  The option may be used twice if
                 both characters are desired.

       -f MIT|LBL|SU
                 Select the output format. MIT is the traditional sim(5) format.  LBL is a variant of it understood by  gemini(1)  which  includes
                 the  substrate  connection  as  a fourth terminal before length and width.  SU is the internal Stanford format which is described
                 also in sim(5) and includes areas and perimeters of fet sources, drains and substrates.

       -y num    Select the precision for outputing capacitors. The default is 1 which means that the capacitors will be printed to a precision of
                 .1 fF.

       -J hier|flat
                 Select  the source/drain area and perimeter extraction algorithm. If hier is selected then the areas and perimeters are extracted
                 only within each subcell. For each fet in a subcell the area and perimeter of its source and drain within this subcell  are  out-
                 put.   If two or more fets share a source/drain node then the total area and perimeter will be output in only one of them and the
                 other will have 0.  If flat is selected the same rules apply only that the scope of search for area and perimeter  is  the  whole
                 netlist.  In general flat (which is the default) will give accurate results (it will take into account shared sources/drains) but
                 hier is provided for backwards compatibility with version 6.4.5. On top of this selection you can individually control how a ter-
                 minal  of  a  specific  fet will be extracted if you put a source/drain attribute. ext:aph makes the extraction for that specific
                 terminal hierarchical and ext:apf makes the extraction flat (see the magic tutorial about attaching attribute labels).  Addition-
                 aly  to  ease  extraction of bipolar transistors the gate attribute ext:aps forces the output of the substrate area and perimeter
                 for a specific fet (in flat mode only).

       -j device:sdRclass[/subRclass]/defaultSubstrate
                 Gives ext2sim information about the source/drain resistance class of the fet type device. Makes device to  have  sdRclass  source
                 drain resistance class, subRclass substrate (well) resistance class and the node named defaultSubstrate as its default substrate.
                 The defaults are nfet:0/Gnd and pfet:1/6/Vdd which correspond to the MOSIS technology file but things might vary  in  your  site.
                 Ask your local cad administrator.

       The  way the extraction of node area and perimeter works in magic the total area and perimeter of the source/drain junction is summed up on
       a single node.  That is why all the junction areas and perimeters are summed up on a single node (this should not affect simulation results
       however).

       Special  care  must  be  taken  when the substrate of a fet is tied to a node other than the default substrate (eg in a bootstraping charge
       pump).  To get the correct substrate info in these cases the fet(s) with separate wells should  be  in  their  own  separate  subcell  with
       ext:aph attributes attached to their sensitive terminals (also all the transistors which share sensistive terminals with these should be in
       another subcell with the same attributes).

       In addition, all of the options of extcheck(1) are accepted.

SCALING AND UNITS

       If all of the .ext files in the tree read by ext2sim have the same geometrical scale (specified in the scale line in each .ext file),  this
       scale  is  reflected  through  to the output, resulting in substantially smaller .sim files.  Otherwise, the geometrical unit in the output
       .sim file is a centimicron.

       Resistance and capacitance are always output in ohms and femptofarads, respectively.

SEE ALSO

       extcheck(1), ext2dlys(1), ext2spice(1), magic(1), rsim(1), ext(5), sim(5)

AUTHOR

       Walter Scott additions/fixes by Stefanos Sidiropoulos.

BUGS

       Transistor gate capacitance is typically not included in node capacitances, as most analysis tools compute the  gate  capacitance  directly
       from  the  gate  area.   The  -c flag therefore provides a limit only on non-gate capacitance.  The areas and perimeters of fet sources and
       drains work only with the simple extraction algorith and not with the extresis flow. So you have to model them as linear capacitors (create
       a special extraction style) if you want to extract parasitic resistances with extresis.

4th Berkeley Distribution                                                                                                               EXT2SIM(1)