Please help me to understand what is the maximum forward voltage for the SPMWH1228FD7WARUVJ

Hello, I am having hard time understanding the datasheet, requesting help.
This is the part:

Maximum forward voltage for that part under stated test conditions would be 3.2v.

I was confused about this A1 A2 A3 A4.
Can you please explain how this works?

Welcome to the forum.

It depends on the bin code (A1 to A4) for the specific part, it can vary from 2.9 (A1) to 3.2 (A4).

Since to drive this properly youโ€™ll be using a constant current source where the voltage adjusts automatically, the maximum value rick_1976 pointed out is the maximum the constant current supply must be able to supply.

What if I want to use constant voltage source (because itโ€™s sooo much easier to get) and also be on a safe side?
Also, how do I know what is the bin code for the parts I order?
Is it random?

Then you have to know the bin code for the part you will use.

If you want use a part with a different bin number later you will need to change the voltage to the new range.

You will also have to accept that the optical performance will be more variable between individual parts and performance over the range of environmental conditions will not be as stable.

Generally driving LEDs via voltage is only suitable for indicators (e.g. power on light) not illuminators.

Typically you can use a constant voltage power supply if the LED has a built in resistor or current limiting device. I believe the best option for this LED, would be to use a Constant Current power supply. As for the Bin Code, it should be listed on the label. If you want a specific Bin Code, you can request it when you are ordering it. If we have the correct one, they will pick that one, and ship it. Otherwise they should contact you if we do not have a match. If you do not specify a specific Bin code, it will be random.

So how do I get this bin code?
Is it possible to order parts with specific bin code?

I know itโ€™s not ideal, but it usually works good enough for the application and adding current limiting parts will make the design an order of magnitude more complicated and expensive.

Iโ€™d rather add 20% more LEDs and have a more resistant resistor than use that 20% of the PCB for current limiting parts.

Using one big constant current supply also feels like something Iโ€™d rather not do, as the whole thing is expected to be 12V@15-20A and I am not confident in my skills to build such a power supply.

Thatโ€™s my plan, to build some resistors in.

So the bin code is the same for the whole reel?

If you order a full reel, it should be the same bin code.

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