# $Id: setup_hold.spec,v 1.17 1999/07/28 14:55:42 ryu Exp $ # Copyright (C) 1999 Robert K. Yu # email: [email protected] # This file is part of Autochar. # Autochar is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2, or (at your option) # any later version. # Autochar is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # You should have received a copy of the GNU General Public License # along with Autochar; see the file COPYING. If not, write to the # Free Software Foundation, Inc., 59 Temple Place - Suite 330, # Boston, MA 02111-1307, USA. #------ SETUP/HOLD TIME CHARACTERIZATION --------------------------------------- #------------------------------------------------------------------------------- # The syntax are the same as the Perl language. Any # valid Perl expression can be used. In fact, this file is # executed directly, so the order of the definitions is # important: Be sure the '&autochar' command, which is actually # a subroutine call to the function 'autochar', is called after # the necessary definitions are made. #------------------------------------------------------------------------------- # Any of the global defaults may be changed here. See # $AUTOCHAR/lib/defaults.pl for a list of what they are. # $spice_cmd = 'hspice'; # $techpath = '/path/to/spice/libraries'; # $spice_corner = 'hspice.ttlh'; # $spice_include = '.include /some/special/include.file'; # $scale_cload = 0.66e-15; # $scale_delay = 0.060e-9; # $trans_period = '2ns'; # etc. #------------------------------------------------------------------------------- # Specify the characterization type. $sim_type = 'setup_hold'; #------------------------------------------------------------------------------- # Specify the name of the spice subckt and the file containing # the spice subckt. $cellname = 'dff'; $spice_netlist = 'dff.sp'; #------------------------------------------------------------------------------- # List of the terms to the cell. Order is unimportant. # Each name is prefixed by a ":x" letter to indicate type: # :i = input # :o = output # :b = biput # :v = vdd supply # :g = gnd # Declare the list manually @termlist = ( 'd:i', 'clk:i', 'q:o', ); # Alternatively, get the term definition from other netlist. # @termlist = &read_spice_terms ("filename", $cellname); #------------------------------------------------------------------------------- # Vary the slewrate of the input clock. # @slewrate = &vary_list(<start>, <incr>, <N>, <units>); # @slewrate = &vary_list(500, 200, 3, ''); # Or specify the explicit list of slewrate values # @slewrate = (0.66667, 1.33333, 2, 2.66667, 5.3333); #------------------------------------------------------------------------------- # Define input buffers. The name of the buffer is a two-port subckt # that will be placed between the input pulse source and the input # term being characterized. Typically, this is a buffer of some sort. # If 'none' is specified, then no buffer will be added. $buffer{'d'} = 'buf'; $buffer{'clk'} = 'buf'; # $buffer{'in3'} = 'none'; # Define any special differential inputs. For example, # in0 and in1 are defined as a differential input pair, # with in1 being the reference. # $differential{'in0'} = 'in1'; # Define any special equivalent inputs. For example, # in0 and in1 are defined as a equivalent input pair, # with in1 being the reference. # $equivalent{'in0'} = 'in1'; #------------------------------------------------------------------------------- # Define the output loads. # Specify the loads for the output(s) that are not being characterized. # If 'none' is specified, then no output loading is added. Use # the words 'cap:', 'res:', or 'subckt:' to indicate an output load that # is an ideal capacitor, an ideal resistor, or a one-port spice subckt. $load{'default'} = 'none'; $load{'q'} = 'cap:10ff'; # $load{'out1'} = 'cap:10ff'; # $load{'out1'} = 'res:1K'; # $load{'out1'} = 'subckt:buf_4x'; #------------------------------------------------------------------------------- # Define the setup and hold constraints. # Define the percentage to use to determine pass/fail: # if the voltage of the internal node is >= the specified percentage # of its final value, then it is said to be passing. If # it is < the given percentage of its final value, then # it is said to be failing. The measurement of the internal # node is made when the clock is at the specified percent # of its final value. $criterion_percent = 0.8; $clock_percent = 0.8; if ($spice_type eq 'smartspice') { # Specify the initial window size, and the number of iterations # this window is stepped in order to find the initial passing # and failing boundaries. Typically in picoseconds. window = 1000; iterations = 20; # Specify the max resolution of the characterization. Once # the window is sized below this value, characterization is # stopped. resolution = 5; # Setup and hold values must be specified as integers # (due to smartspice implementation reasons). The actual values # is scaled by this value. Typcically 1e-12 is used for picoseconds. setup_hold_scale = '1e-12'; } else { # default hspice: # Define the relative input parameter variation # and relative output results function variance for convergence. # See the hspice 'Optimization' chapter for details. $relin = 0.001; $relout = 0.001; # Define the range of minimum and maximum setup values allowed. # Setup time is defined positive before the clock. @setup_range = ('0', '1ns'); # Define the range of minimum and maximum hold values allowed. # Hold time is defined positive after the clock. @hold_range = ('0', '1ns'); } #------------------------------------------------------------------------------- # Characterization command. The general form is: # &autochar ( <d>, <clktype>, <clk>, <qtype>, <q>, <ctype>, <c>, [ <tie>, <unused>+] ); # # <d> = name of the flop data input term # <clktype> = either 'rising' or 'falling' clock edges # <clk> = name of the flop clock term # <qtype> = either 'inverting' or 'non_inverting' w.r.t. d # <q> = name of the flop data output term # <ctype> = either 'inverting' or 'non_inverting' w.r.t. d # <c> = name of the internal criterion node # # Optional: # <tie> = how to tie the other inputs, either 'tie_high' or 'tie_low' # <unused>= name(s) of the inputs to be tied. These are regular # perl expresssions. Be sure to write brackets [ and ] # as \[ and \], respectively. < and > are ok. # # characterize all inputs &autochar ('d', 'rising', 'clk', 'non_inverting', 'q', 'inverting', 'n10'); #------------------------------------------------------------------------------- # In some cases, it is desirable to skip the characterization of certain arcs # and to copy the data from another set of arcs instead. The general form is: # ©char (<d>, <clktype>, <clk>, <refd>, <refclk>); # ©char ('d', 'falling', 'ph1_b', 'd', 'ph1'); # Must return a value to make perl happy. 1;