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Putdevmod(1ICD) places a device model description
into the circuit database. One or more filenames may be
given as argument, each containing exactly one device model
description.
For new projects with xcontrol use the program
xcontrol to set and list the cell device status. In
that case, the program putdevmod only adds the
"devmod" file and does not set the device
status.
A device model description contains a description of the
name of the device, a description of its terminals and
(optionally) a simulation model for the device (currently
only SPICE models are supported). The device model
description is used by other programs to detect which cells
are network primitives (e.g. by the layout-to-circuit
extractor space(1ICD) and by programs that retrieve
circuit descriptions from the database) and/or to collect
simulation input.
To remove a device model for a cell, use
device(1ICD) with the option -u.
The syntax of an input file for putdevmod is as
follows: On the first line the keyword "device" is
specified followed by the name of the device. On a next line
the keywords "begin" and "spicemod" are
specified to denote the beginning of the SPICE device
information. The next lines are considered to be SPICE input
that can directly be appended to a SPICE network description
in order to form the model description of the device. The
end of the SPICE model description is denoted by a line that
contains the keyword "end".
In the part of the input file that is used as SPICE
input, the terminals, a possible bulk potential and a prefix
for instance names for the device, may be included as SPICE
comment. This is done by specifying them on lines that start
with the comment character "*".
To specify the terminals, use the keyword
"terminals" followed - on the same line and
separated by spaces and/or tabs - by the names of the
terminals. The order in which the terminals are specified in
this file must agree with the order in which the terminals
are required in the SPICE circuit description (see the Spice
User's Manual). The following terminal names are used
for the standard devices: ""g", "d"
and "s" for the gate, drain and source of
field-effect transistors, ""c", "b"
and "e" for the collector, base and emitter of
bipolar transistors, and "n" and "p" for
the terminals of resistors and capacitors.
A bulk voltage (if appropriate) may be specified by the
keyword "bulk" followed by a floating point
number.
A prefix character for the instance names of the device
is specified by the keyword "prefix", followed by
a character.
By using putdevmod the user can easily perform
extraction of devices that can not be recognized with the
built-in device extraction algorithms of space(1ICD).
A requirement for this is that the layout description of the
device is stored in separate cell in the layout view. Using
putdevmod a device model is then stored into the
database that has a same name as the name of the layout cell
and a list of terminals that is similar as, or a subset of,
the list of terminals of the corresponding layout cell. The
layout to circuit extractor space will consider these
devices to be leaf-cells whose contents should not be
extracted, but that should be included as primitives in the
network description instead.
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