Is there a standard that defines that the marking actually has to indicate the cathode?

SMD LEDs normally have some kind of marking. We recently had 300 PCBs manufactured where each had 32 LEDs of those. However, the assembly house placed all LEDs in reverse. The cathode is not consistent with the marking of the actual LED that was mounted. Is there a standard defining this?

PCB Assembly, PCB Testing
December 6, 2023

No. It is entirely up to the component manufacturer. When the PCB is manufactured, some companies will ask that component placement overlays be given. Designators are provided. And polarity marks for all polarized components are shown.

It’s also a good idea to make a couple of test boards and hand solder and get familiar with the components to identify this kind of issue, prior to sending in large batches to get assembled.

#PCB Assembly #PCB Testing

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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