What is the proper zero orientation for a SMT LED?
According to screaming circuits and IPC-7351, the cathode should be on the left for a molded diode. HOWEVER, when I use Altium's component wizard to create a diode, it places the cathode (K) on the right! I would assume that IPC-7351 would be correct, but I don't understand why the Altium default would be backwards.
Does it depend on the manufacturer? How does the assembly house know which way is correct?
For reference, I am looking at the OSRAM LS R976, which has the cathode towards the holes on the tape.
Unrelated: Why does the search in the top right corner return different (and in this case, worse) results than the search that comes up when you click ask question?
Best Answer
You should use the IPC-Compliant component Wizard insted of the standard Component Wizard.
From here you may select the polarity pin position.
If the IPC compliant footprint Wizard does not show up in your "Tools"-Menu you have to install the plugin first: