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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) rep-
     resentation 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  out-
	       file.

     -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 output.
	       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 terminal  of
	       a  specific  fet  will be extracted if you put a source/drain at-
	       tribute. 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).  Additionaly to ease
	       extraction of bipolar  transistors  the	gate  attribute  ext:aps
	       forces  the output of the substrate area and perimeter for a spe-
	       cific 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  sub-
	       strate.	 The defaults are nfet:0/Gnd and pfet:1/6/Vdd which cor-
	       respond 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  at-
     tached  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 geomet-
     rical 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  cen-
     timicron.

     Resistance  and capacitance are always output in ohms and femptofarads, re-
     spectively.

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 sim-
     ple 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)

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