Screaming Circuits: Push-me Pull-you LEDs


Push-me Pull-you LEDs

I may never get tired of talking about LED and diode polarities. It's so much fun. Not long ago, I wrote about two LEDs from the same manufacturer, marked with opposite polarities. I recently ran into another one, but at least this one tells you on the same datasheet. This image is an actual unmodified clip from the datasheet.

LED confusing polarityI can't for the life of me understand why this would be done on purpose. I could maybe understand if one was designed in a different building, but it couldn't have been too hard for someone to say: "Hey - wait a minute..." before sending these things off to manufacturing.

Of course, maybe they built a million before noticing and then just decided it would be easier to change the datasheet. Regardless, it's kind of nuts in my opinion.

The other thing here is that, while you can generally get away with the indicators "+/-" on an LED, you can't with all diodes. Think Zener and TVS.

Duane Benson
Matter + antimatter makes what?
Does it really matter?
Does anybody really know what time it is?


Bicolor: You just have to write your product documentation to take care of the problem:

"The charging light will be red or green when the device is charging, and will switch to green or red when it is not. It is, under all circumstances, either red or green*.

[*: Except when it isn't, such as when the product is turned off, without power, defective, or you got tired of the bright-ass LED and taped over it.]"

What do they do for bicolor LEDs?

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