Monday 27 January 2014

Additional I/O Pins HOW to GET ...

How to get an additional pin to an existing one to have an I/O pin for the same net on different places.
There is no menu command or text command to do that. You can just do it by modifying a DEF or Floorplan-File in the following way (DEF shown):
 
PINS 2 ;
- netout + NET netout + DIRECTION INPUT + USE SIGNAL
 + LAYER Metal2 ( -280 0 ) ( 280 560 )
 + FIXED ( 23100 60000 ) S ;
- netout.extra1 + NET netout + DIRECTION INPUT + USE SIGNAL
 + LAYER Metal2 ( -280 0 ) ( 280 560 )
 + FIXED ( 24100 60000 ) S ;
END PINS

If bus pins have to be doubled the syntax is the following (the extra1 extension has to be added before the bus number):
 
PINS 2 ;
- netout<0> + NET netout + DIRECTION INPUT + USE SIGNAL
 + LAYER Metal2 ( -280 0 ) ( 280 560 )
 + FIXED ( 23100 60000 ) S ;
- netout.extra1<0> + NET netout + DIRECTION INPUT + USE SIGNAL
 + LAYER Metal2 ( -280 0 ) ( 280 560 )
 + FIXED ( 24100 60000 ) S ;
END PINS

Read in the modified DEF and you will see the additional pin.

2 comments:

  1. hi kirtesh,
    if we are adding a double pin in which scenario it will be helpful?
    Regards
    phani

    ReplyDelete
  2. Hi phani,

    if you are doing full chip LVS , then you need some I/O ports to be formed , to avoid floating gate error. So we can create those pins by Encounter command also or we can go by this method.

    now one more thing suppose if you have one version of memory and suddenly there is a change in memory pins then to verify the connectivity you can go like this.


    Thanks
    Kirtesh

    ReplyDelete