Lol... So the 3V rating is just there if you don't want to use a current limiting resistor?
ahhh that's a little different if that's all that's available then yes your thinking is correct!
soorry just trying to ascertain the thought process is all...
The proper resistor for the rated voltage will be included in the part.
For the 3V part, the included resistor is likely to be around 100R.
For the 12V part, the included resistor should be about 1k.
LEDs should never be used with a voltage supply without a current limiting resistor.
They can be used with a current source of the correct value, without a series resistor.
Last edited:
Alright.. So I'll just make the assumption that the resistor is in the package even though it's not shown in the datasheet I guess.
Yes, the data sheet is written by and for less technical people, who don't care or want to know
about such details that are unnecessary for using the part.
about such details that are unnecessary for using the part.
For anyone who comes across this thread in the future - this is indeed the case. I put together a little 3V regulator, and it lights up with no added current limiting resistor. I'm running directly from a 3Vdc supply. It also appears to pull 20mA @ 3V, so there must be ~150ohms of resistance in line internally.
I should add too, it's an extremely nice switch. Highly recommended.
Last edited: