Log-To-SPICE Conversion
DESCRIPTION
Harold Levy of Caltech modified the LOGNTK program to create a
new program, LOGSPC, that creates SPICE decks instead of .ntk files.
The tool is used identically to LOGNTK, so the manual section above
describes LOGSPC also. The command to invoke the tool is :logspc, and
configuration information is in the file lib/logspc.cnf. The FET7
series works with LOGSPC, supported by the LAMBDA command. The FET
models NSPC1 and PSPC1, contributed by Bhusan Gupta at Caltech, are
perfect for use with LOGSPC. These gates also simulate in analog;
however, these models are considered "experimental" as opposed to
"standard" models in analog, and are not supported by the chipmunk
maintainers.
LOGSPC ADDITIONS
A few additional commands have been built into LOGSPC to better
support SPICE capabilities. Note that the SIZE and STRENGTH commands
of LOGNTK are ignored in LOGSPC, and that the following commands are
used instead:
NBULK: signal-name
PBULK: signal-name
These commands assign explicit names to the implicit
bulk terminals for 3-terminal FET (e.g. p/n-FETs 4 and 5)
and bipolar (e.g. NPN1, PNP1) models. The signal-name
is output in capitals unless quoted.
LAMBDA: number
This command assigns an explicit lambda value (in
microns) to the FET7 model series.
CHLEN: number
This command assigns an explicit channel length (in
microns) to FET models using w/l ratios (e.g. p/n-FETs
4, 5, and 6).
PRE: filename
POST: filename
Specifies a file for inclusion into .spc files before
and after netlist.
Also note that as of LOGSPC version 0.5b the ability to extract VDIFF
gates is provided. This feature may be shut off with the command
LOGSPC: IGNORE VDIFF
Finally, the TRANS command has been extended, to supporting adding new
gate types to logspc, as shown in the example below.
EXAMPLE
Copy the files chipmunk/log/lib/{spctest.lgf,pre.spc,post.spc} to your
directory, and examine and run logspc on spctest.lgf, to see the features
described above in action.
FILE CONVERSIONS
The supplementary toolkit includes companion programs to LOGSCP,
that simplify using LOGSPC output with other tools. These tools are located
in the spc-tools subdirectory of the toolkit. Three scripts are included:
sf: Flattens hierarchical LOGSPC (version 1.0) output.
ss: Converts output from "sf" into UCB SIM format for use with
UW's "gemini" layout-versus-schematic (LVS) comparison program.
ucbsim: Appends "format: UCB" to the first line of SIM files generated
by ext2sim.
- Email
- lazzaro@cs.berkeley.edu
- Phone
- (510) 643 4005
- SMail
- UC Berkeley / CS Division / 387 Soda Hall / Berkeley CA 94720