Gate Swap in Multisim

[pcurt]

Is it possible to perform gate swapping between different subcircuits in Multisim?  I've figured out how to do it in Ultboard, but it's very time consuming to swap those gates and backward annotate them.  For instance, in my particular circuit I have 4 transistors: 2 p-type and 2 n-type.  They are arranged in pairs so I am using IC packages which contain 2 gates (1 p-type gate and 1 n-type gate).  I would like one pair of transistors assigned to U1A and U1B and the other pair of transistors assigned to U2A and U2B.  Sometimes, these transistors are swapped within a subcircuit.  Other times a particular subcircuit uses 4 different physical parts.  I don't necessarily care that the REFDES are sequential in my circuits.  I would just like to see 2, and only 2 parts used per sub-circuit, and each of their A and B sections assigned to either the top half or the bottom half of that subcircuit.

I've checked out the Rename/Renumber Components dialog, but the automatic renumber and gate optimizers functions don't produce the results I would like.  There isn't enough information in the table to renumber the parts by hand.  If I sort the table by the first column (the RefDes path), I see 4 parts listed - 2 section A's and 2 section B's.  There are 2 combinations of assignments and I have a 50/50 chance of picking the wrong way.

I would love to have a gate swap feature similar to that in Ultiboard.  I select "Gate Swap" in a menu.  Click on a part in one subcircuit.  Then switch to another subcircuit and click on a similar gate.  Multisim will switch the RefDes of those gates.  Either that, or if I could somehow specify a part group for these subcircuits perhaps the gate optimizer could group my parts more wisely.

Is there another way I can do this to save time?

Thanks.

Petersen

[_user32]

Petersen,

I have been playing around with this and I believe I understand what you are recommending.    There are 2 parts to this.   First it appears that you are seeing an existing known issue about reference designator auto-numbering in subcircuits (hierarchical blocks).   (Currently auto numbering of refdes parts within a HB is not optimal and it is currently difficult to correct - as I think you are seeing).   I believe we are looking at improving this so I will check on the status.

The second recommendation is a better method of swapping subsections of a component (as this may come up in a variety of situations).  Currently the best method allowed is to replace a component (for instance using the replace function and mapping to existing component (but the refdes/section has to be available).   You are correct the Gate Optimization tool (with Part Renumbering) does not seem to do this automatically to great satisfaction.

My suggestion is if the component is already placed, do a swap.... shown step by step with this circuit...  (using the ND89956A which is a dual N Channel)...

Right click on Q3B for instance and hit "Replace Components..."

(yes I know it can be tedious if you have to completely browse for component again)

...

Select Q2B (In this case I am trying to match it up with Q2A directly above)...

and then right click on Q1B and replace...

with Q3B (so it matches up with Q3A above)...  in this case the refdes are not sequential but you said this was not as important as doing the gate optimization to verify that there are not unused gates being used.

In the case with HBs, you may just want to replace each of these component sets (each pair of 2) and replace the first with a new part refdes and match the others within the same HB with section B, etc...

Also I do understand this is tedious and would be better implemented with a tool (maybe within spreadsheet or an improved Gate Optimizer) so I will also recommend a feature request to have a better method for swapping (rather than having to replace) each subsection within a circuit / heirarchical block.

If I have misunderstood your question in some way please let me know.

Regards,

Pat Noonan

BDM - EWB Group

[pcurt]

Pat,

Thank you for your reply.  This is exactly the situation I encountered.  Thank you for the step gy step guide.

Alternatively, I had an idea for another improvement.  Would it be possible to support import & export functionality in the Gate Optimizer window?  If I could export my list of gates to my favorite text editor, or spreadsheet program, I could edit the lists by hand or even with a simple Perl script before importing a revised list back into the window.  I understand this would be less automatic as it would require another tool, but it would add greater flexibility for making repetitive changes on a design with many subcircuits / HBs.

[_user32]

Petersen,

I am not sure to what extent we could open up this - as we would need to ensure we don't corrupt the circuit in our new WYSIWYG (what you see is what you get) naming convention.   However, I do see the value in your request and I will add this to the overall feature improvement request.

Regards,

Patrick Noonan
Business Development Manager
National Instruments - Electronics Workbench Group