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short a particular device terminals while probing a net

GTRam

Hi,

     I'm looking for a way to short the terminals for a particular instance while probing in the schematic. The following is the requirement

1. I have some device kind of ammeter in the schematic which separates the net in terms of schematic connectivity but electrically they are the same nets.

2. So while probing the net in schematic, the probe stops at the first appearence of ammeter. 

3. I wanted the probe to jump such devices and continue probing.

I was partially successfull  thruough skill as follows

1. find the instances connected to the desired net

2. Look for an ammeter and get the other terminal net

3. repeat 1 and 2 untill the bottom of the hierarchy.

 

The problem is my script takes longer timer to probe since I have written it in a recursive manner and dbOpenCellViewByType is a time consuming step. My question is

Is there any other way to do this or can we modify how the probe works? There are no options under F3

How can I speed up hierarchy travel?

 

Thanks

GTRam

  • This can be done from IC615 ISR7 (I think) onwards. Search in cdnshelp (Help->Documentation in the CIW) for "Probing a feedthrough net" and you'll find the relevant section which tells you how to turn this on and register the "feedthrough" device.

    Having done that, you can probe a net and it will probe through your ammeters.

    Regards,

    Andrew.

  •  Hi Andrew,

         I use IC615.500.17 virtuoso and could not find anything related to what you have mentioned. Could you please give me the exact procedure name for this?

     

    -Thanks

    GTRam

     

  • Ah, it only appears to be documented in IC616. Here's the relevant part of the docs:

    In order to allow feedthrough probing, you need to do the following:

    1. Enable the feedthrough using probeTraverseFeedThrough flag.
      envSetVal("graphic" "probeTraverseFeedThrough" 'boolean t)
    2. Register the feedthrough using the ciRegisterDevice function.
      For example, if you want to short PLUS and MINUS terminals of res, you need to enter the following:
      ciRegisterDevice("probeShort" '( (nil "res" nil (nil shortedTerminalMap ( ("PLUS" "MINUS") ) )) ))

    Regards,

    Andrew.

  •  Thanks Andrew, I will check with IC616. 

    If you have any workaround like what I'm trying to do please let me know for IC615.

  • Don't get me wrong - it should work in IC615 - it's just not documented. Note, I didn't actually try it (lack of time), but the environment variable is definitely defined there...

    Sometimes things added during hotfixes take a while for the docs to catch up.

    Andrew.

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