What is the proper zero orientation for a SMT LED?

According to IPC-7351, the cathode should be on the left for a molded diode. However, when I use component wizard of my suppliers to create a diode, it places the cathode (K) on the right. Does it depend on the manufacturer? How does the assembly house know which way is correct?

November 23, 2023

We prefer cathode on the left, as per the standard, but typically rely on silkscreen or customer input to determine the proper orientation.

Oliver Smith

Oliver is an experienced electronics engineer skilled in PCB design, analog circuits, embedded systems, and prototyping. His deep knowledge spans schematic capture, firmware coding, simulation, layout, testing, and troubleshooting. Oliver excels at taking projects from concept to mass production using his electrical design talents and mechanical aptitude.

Oliver Smith

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What is the proper zero orientation for a SMT LED?

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