Here is an annoyance I'm experiencing often when it comes to gschem. When I instance an symbol in, whether it be a transistor, a subcell, or any other random component, all of the attributes are saved in the schematic file instead of inherited from the symbol file. This may not seem like a huge concern but imagine that you have a fairly large hierachrical design where you instanced transistors in from a symbol file 100's of times. Lets say the symbol properties of that symbol are refdes=M?, l=0.13u,w=1u,device=n3t,bulk=vss,value=n. Now, I bring in a new model for that transistor called nmos instead of n. So I go and change the symbol file from value=n to value=nmos. But whoops, the attributes are local so now I have to open up every schematic and changes the transistors one by one instead of editing on symbol file and having my whole design inherit the attributes. Now with that said, I know inheriting ALL attributes wouldn't make any sense. For example you can't have the refdes and w/l inherited. However, there should be some way in the symbol file what to inherit something by default and making the local version optional. For example the way other CAD tools I know of handle this is that each instance has a master attribute and a local attribute. If there local attribute is blank, it inherits from the master attribute. If the local attribute is filled out, then it takes that value of the master. refdes should me mandatory, all else should be optional.
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