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Bug: SDPT Switch stuck on pin 3 toggle in sub circuits

I am using Multisim 11.0 and believe that I have found a bug:

 

If I go into anyone of my subcircuits and attempt to utilize an SDPT switch, it becomes stuck with pin 3 (the lower pin on the two-pin side) connected to pin 2. I can start my simulation with the switch with pins 1 and 2 connected (diagonoal) and it outputs the correct voltage, but as soon as I switch to 3 and 2 (straight across), I cannot go back.

 

When I copy-paste the following circuit onto the top layer of my design however, it works fine.

 

The circuit I made to confirm this error was:

 

-Pin 1 of SDPT to 5v DC to Gnd

-Pin 2 to 1k resistor to Gnd

-Pin 3 to Gnd

 

I have also verified that the voltage doesn't matter by reversing pins 1 and 3.

 

Please confirm that this is a bug with the component that will be resolved?

 

Thanks,

 

-AM

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Edit:

 

It appears that other switches exibit this same bug in subcircuits. I have attached a picture of how the switch looks rather confused when you click upon it and keep the cursor hovering over it.

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Hi aamailhot,

 

Is it possible for you to upload your circuit because we need to see what could be causing this behaviour.

 

Regards,

Tayyab R,
National Instruments.
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Tayyab,

 

Unfortuantely the design is proprietary, HOWEVER I think I have narrowed down the cause of this bug. Here are the generic steps to recreate the bug, and how to rectify it (soft of):

 

1. Create an arbitrary subcircuit, SC_1. With a switch SOMEwhere in the circuit. It could be totally isolated from the inputs or anything, doesn't matter (my example circuit above would be a valid choice).

 

2. Make a copy of SC_1, SC_2 on the same top-level of the schematic.

 

3. Run the simulation, attempting to opperate the switch in SC_1. It fails. Interestingly, the same switch in SC_2 seems to work fine...

 

4. Delete SC_2 and repeat 3) above. The original switch, in SC_1 works fine.

 

 

My thoughts: It appears that the most recently made clone of an SC is the 'active version' and all others have some sort of lag that causes the malfunction? Apparently the fix is to plain not have switches in subcircuits, but this seems rather limiting (even though it is probably good design process, to only have switches on the top-level of a design).

 

Please confirm/deny/comment.

 

Thanks!

 

-aamailhot

 

P.S. I would enjoy this functionality so that I may debug the internals of SC's without having to jump back and forth between multiple levels of the circuit (i.e., treat the SC and its own end-to-end circuit, which it SHOULD be).

 

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Hi aamailhot,

 

I tried the scenario you suggested and I did see an issue with the switching. The problem is because of copying and pasting sub-circuits.  I will file a bug for this issue.

 

At this time, the workaround I can suggest is to copy and paste the components which you will place in the sub-circuit in the original design and then create the sub-circuits for each of them. It seems to work fine when you do it this way.

 

Hope this helps.

 

Regards,

Tayyab R,
National Instruments.
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