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PACK_SHORT Property on Heterogeneous Symbol Causes Error

grmnrsbonini

Working in Capture CIS 17.4, I've created a heterogeneous multi-part symbol to separate the power and signal blocks of a component.  I've added the PACK_SHORT property to the symbol to tie the thermal pad (EPAD) to the negative power pin (V-).  The EPAD and V- pins are on part 'B' of the symbol.  Let's assume the part refdes is U1.

Once the symbol is placed on the schematic, I get an error stating the V- pin in the PACK_SHORT property doesn't exist on U1A.  There is also an error stating that there is a pin count mismatch between the U1B symbol and the footprint, however U1A+U1B has 9 pins, and so does the footprint.

I assume both of these errors stem from the same underlying issue.

Is there a way to resolve these errors or can PACK_SHORT *only* be used with monolithic symbols?

Thanks!

Parents
  • AyushD
    0

    The limitation of using PACK_SHORT on a heterogeneous part is that pins on different sections of heterogeneous part can't be shorted through pack_short.

    Check if you are shorting pins that are present in different sections of the part.

  • grmnrsbonini
    0 in reply to AyushD

    That is not the case here.  Both pins, EPAD and V-, are on the same Section (B) of the part.  Whereas the error message specifically calls out Section 'A'. 

    Does the PACK_SHORT property need to be restricted/isolated to Section 'B' somehow?  I have looked for something like this but not found anything.

  • AyushD
    0 in reply to grmnrsbonini

    If you define the property at library level, it would have got applied to all the sections. You need to delete its value from the other section if it is defined there as well.

  • grmnrsbonini
    0 in reply to AyushD

    Ok, so I did try deleting this property from Section 'A' of a part placed in a schematic and get the following error:

    Since this property is defined in the library, it can't be deleted at the schematic level, and if it can't be deleted then the error on Section 'A' can't be resolved.  My conclusion then is that the only option is to add PACK_SHORT at the schematic level to the specific section every time you want to use the part, especially if the superfluous pins have been hidden (the whole point of PACK_SHORT).  Essentially there is no practical benefit to using PACK_SHORT on a heterogeneous part.

    Is this correct?

Reply
  • grmnrsbonini
    0 in reply to AyushD

    Ok, so I did try deleting this property from Section 'A' of a part placed in a schematic and get the following error:

    Since this property is defined in the library, it can't be deleted at the schematic level, and if it can't be deleted then the error on Section 'A' can't be resolved.  My conclusion then is that the only option is to add PACK_SHORT at the schematic level to the specific section every time you want to use the part, especially if the superfluous pins have been hidden (the whole point of PACK_SHORT).  Essentially there is no practical benefit to using PACK_SHORT on a heterogeneous part.

    Is this correct?

Children
  • AyushD
    0 in reply to grmnrsbonini

    Just try to delete the value of the property from that section not the property itself

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