The directory contains all the files needed in ADDITION to
GSPICE to characterize standard cells.

PERL programs:
---------------
 sim_gen     -> run on .lib file to create .gs file for GSPICE
 lib_merge   -> run by .gs file to merge simulation results back into .lib

GSPICE macros:
---------------
 char_ff.gs    -> routines used to characterize flip-flops 
 char_logic.gs -> routines used to characterize combinatorial cells
 char_cap.gs   -> routines used to calculate pin capacitance
 char_base.gs  -> basic routines utilized in other files


THE PROCESS:
--------------
  1) Generate cell .lib file by hand (see examples in directory)
  2) Run sim_gen to create a .gs file
        Ex: sim_gen ND2P.lib   -> creates ND2P.gs
  3) Runs GSPICE on the .gs file to run simulations and
     to merge the results back .lib to create new .up_lib
        Ex: gspice /BATCH ND2P.gs
              -> runs simulations to create ND2P.sim_stuff file
              -> merges results back into ND2P.lib to create ND2P.up_lib

  Note: Measurement conditions will probably need to be updated
        before the scripts are used. See the end of this file.

   
Example Cell Template Files:
-----------------------------
  setup.mod     -> example file to setup eldo simulation conditions
  FD4TQP.lib    -> a flip-flop
  LXFD1S8QP.lib -> flip-flop with 8-1 mux with unencoded mul selects
                   (note: notice the way _REM timing was used to 
                          measure the select timing)
  IV.lib         -> standard inverter
  ND2P.lib       -> standard 2-input NAND
  NEWEO3P.lib    -> standard 3-input XOR
  LXAN2MX21P.lib -> 2-input MUX with logic (NAND gate) merged into MUX



Modifying Measurement Conditions
----------------------------------
Before the scripts are run the measurement and simulation conditions
will most likely need to be updated.  The data which need to be
updated are at the top of the files mentioned.  The files are:

   char_base.gs  -> a) update VDD and TEMP values
                    b) update "lu_template_table" measurement matrix points

   setup.mod -> gets included into every simulation run. Update simulator
                .options commands and process model include statements.

   char_logic.gs -> update measurement points for rise and fall transitions
                    as well as waveform the points cell-delay 
                    measurements are made at. 

   char_ff.gs -> same as char_logic.gs

                    

 







