Replacing a footprint wihtout re-netlisting ***Urgent***

If the pad locations are the same...If it is in Layout you can select the part and then select a different footprint.  If it is in PCB Editor you need to have an alternate footprint in the netlist.  (You can not replace the footprint as in Layout...I know not good)  After you have added the alternate to the netlist and imported it, delete the footprint from the board.  You can not swap them you must delete the original and place the alternate footprint.  One nice thing about PCB Editor is you can delete the part and not affect the traces.  If the pads are not in the same spot, you just need to reconnected the end points of the traces to the pads.

 Good luck,

Ken

KEN13 said:

If it is in PCB Editor you need to have an alternate footprint in the netlist. 

How do I put an alternative footprint in the DSN ,create aother netlist, and have no parts placement affected on the BRD?  The last time I tried this, the board went back to all "new" parts ripped up and not placed. Had to re-place them all over again.

I guess that you are reloading the netlist from within Capture? If so, you need to ensure that you set the "Input Board" to the current BRD file so that the netlist is loaded onto the board in its current state. IF the "Input Board" is blank, you will be loading the netlist onto a "blank" board and everything will be unplaced, somewhat like your description of what you are seeing. "Generally" a "minimal amout" of stuff will be removed once the board has been started.

First save a copy of the original board.

Open up the design.  Double click on the part to open the property editor.  Change the Filter by to Cadence-Allegro.  Add you alternate symbol(s) to the ALT_SYMBOLS box.  Switch back to <Current Properties> if you wish.  Close the window.  Save.  Not sure what happened the first time you brough in the netlist.  It sounds like the original link was lost or perhaps this was a translated board???  Since you brought in the new netlist prior and placed everything after it was ripped up importing a new net list should not change any symbol or trace place on the board.  Now delete the component and use the alternate footprint.

Ken 

oldmouldy said:

If so, you need to ensure that you set the "Input Board" to the current BRD file so that the netlist is loaded onto the board in its current state

That's what I did (I think) .  I started with an old BRD, created a new netlist from the new DSN in capture, then let  it fly.  The second time I needed to do it was because some footprints were incorrect.  So I modified the pcb footprint in capture, resaved and netlisted. When I went to the BRD, it ripped up ALL the components from the first go around.  That is to say the components that were new to the design because of a new schematic. Not EVERYTHING.

I spent quite a bit of time placing and routing and it all got ripped up when I reloaded the DSN. Suggestions?