10 Replies Latest reply on Mar 28, 2018 8:59 AM by robert_davies

    Autoassign refdes in dx-designer


      I want to add a new circuit to the existing schematic. While placing the symbol in the schematic is there any option to automatically assign refdes based on the increment of last assigned refdes? For eg: If there are 4 capacitors (C1, C2, C3, C4) present in my schematic and I have to add a new one while placing it should be number as C5 automatically.

        • 1. Re: Autoassign refdes in dx-designer

          No there is no on-the-fly packaging as you place parts into the schematic, packaging is a batch process either through the Pacakger (Xpedition flow) or the PCB Interface (PADS/Netlist flows).

          • 2. Re: Autoassign refdes in dx-designer

            Thanks for the reply robert. By having all the symbols with refdesprefix_? will automatically assign while package? For eg: I have ten newly added capacitors for those I have to place redes as C? before package? If so package will allow to package?

            • 3. Re: Autoassign refdes in dx-designer

              You don't have to place C? on the symbols but most people do so in the symbol editor so they can define the location of the reference designator when it is applied. You assign Ref Designator = C? (REFDES=C? in Netlist flows) in the symbol definition by editing the symbol in the symbol editor, then when it is packaged the designator will create a refeference designator begining with C and incrementing, so C1, C2 etc. Obviously if C1 and C2 already exist it will start at C3.

              If you don't pre-assign the Ref Designator (REFDES) and its position on the symbol the packager will still assign C1, C2 etc based on the definition in the Central Library and the Ref Des prefix, and the position of the property will be bottom left of the symbol which might not be what you want.

              • 4. Re: Autoassign refdes in dx-designer

                Robert, I don't think he wants to change the new circuit RefDes numbers to "?",

                nor is he asking about where the RefDes appears on the page in relation to the symbol.


                I think he wants to add an existing circuit to his design that already has RefDes assignments.

                How do you make sure that it is the circuit you are ADDING that gets reassigned, and not your design?
                In other words, if you have a C3 in your design and you add a block from another design that has a C3,

                how do you make sure that it is the new block that gets an updated RefDes and not your existing C3?


                I THINK that is what he was asking, but if it isn't, I still want to know..! (smile)

                • 5. Re: Autoassign refdes in dx-designer

                  I don't have blocks. For eg: If I have C3 already in schematic and adding another capacitor, it should automatically be numbered as C4 while place.

                  • 6. Re: Autoassign refdes in dx-designer

                    To answer Jack:

                    I understand the question which is whether the reference designator would be incremented as the symbols are placed into the schematic, the answer to which is no.

                    The follow on question was in two parts, firstly if the symbol has a Ref Designator such as C? will the packaging process succesfully assign sequential reference designators, the answer to which is yes as the ? is treated as a wild card.

                    The second part to this was whether it was necessary to have C? on symbols, the answer is no, at least not in the Xpedition flow, the prefix is defined by the Part Definition (PDB) in the library, the n? notation comes from the netlist flow but works in either flow.

                    The elaborate answer I gave was to indicate that adding the Ref Designator to the symbol aided in positioning when the part is packaged, in the Xpedition flow this can be in the form of a simple placeholder (property without a value) or with a value including a wildcard such as C? (which is required for the netlist flow).

                    To answer the question about clashes - the packager will inform you of any conflicts and depending on the settings you use you can enforce repackaging of the design to avoid conflicts.

                    • 7. Re: Autoassign refdes in dx-designer

                      (Using Expedition VX 1.1) - Think should be the same for later versions, but don't know about PADS flow.


                      With the SETUP --> SETTINGS menu, under ADVANCED

                      there are two settings

                      Preserve packaging info on copy and

                      Preserve packaging info on cut


                      By having these selected or not selected then if you either copy or cut another section of circuitry to a new schematic it will either maintain existing ref designators (not exactly what is required here) or forget them and return the symbols to default "?" with this option then once design is packaged new unique ref designators will be allocated.


                      • 8. Re: Autoassign refdes in dx-designer

                        (ok sorry. I only saw one question and was reading through looking for the answer to that one question, because I would like to know, too!)

                        • 9. Re: Autoassign refdes in dx-designer

                          (THANK YOU!)

                          • 10. Re: Autoassign refdes in dx-designer

                            For blocks you instantiate you can use the Ref Des renumbering capabilities within the tools, Ref Des Start, prefix, increment etc. Look them up in help.