si_xtalk_double_switching_mode

NAME
       si_xtalk_double_switching_mode
              Controls  the double switching detection during the PrimeTime-SI
              timing analysis.

TYPE
       String

DEFAULT
       "disabled"

DESCRIPTION
       Double switching detection mode can have one  of  these  three  values,
       "disabled",  "clock_network"  or "full_design". When this mode is "dis-
       abled", the default  mode,  this  double  switching  detection  is  not
       enabled.  When  this  variable  is  enabled  (set to "clock_network" or
       "full_design"), during update_timing PrimeTime-SI checks  that  whether
       crosstalk bump on the switching victim could cause the output to switch
       twice (and cause a pulse) instead of of desiered single signal propaga-
       tion.

       To  detect  the  potential double switching in the clock network, which
       could cause the double clocking (where the clock could switch  twice on
       a  the  sensitive  edge) or false clocking (where the switching bump on
       the non-sensitive edge could actually latch the state), set this  value
       to "clock_network".

       To  detect  the  potential double switching in the data path as well as
       clock path set this variable to "full_design".  Double switching  on  a
       data path is less severe then double switching on the clock network.

       The  double  switching  detection needs CCSN library information on the
       victim load cell.

       After the update_timing user could access these information in two ways
       1)  by  command  report_si_double_switching or 2) by the net attributes
       si_has_double_switching &  si_double_switching_slack.   Refer  the  man
       page  of report_si_double_switching for the command details. The victim
       net attribute si_has_double_switching is true  when  ever  there  is  a
       potential  double  switching  on  any of the load pins.  The victim net
       attribute si_double_switching_slack has the bump  slack,  reducing  the
       switching  bump  by that much amount could remove the double switching.
       If the victim net  doesn't  cause  double  switching  si_double_switch-
       ing_slack  will be "POSITIVE". If the victim net load pins doesn't have
       CCS-Noise model information, the attribute will be reported as "INIFIN-
       ITY".

       The victim nets having the double switching is automatically reselected
       to higher iteration so that they could be reanalyzed with more accurate
       analysis.

       The double switching happens when, the switching bump & transition time
       are large and fed into driver which  strong  enough  amplify  this.  To
       avoid double switching either of them can be reduced.