Look at the 3mm and 5mm LEDs from different companies as anything high powered isn't even close to that drive current. As idleprocess said...your probably not going to find green and blue LEDs in that voltage range. You'd probably be hard pressed to find red in that range too. What is you application as it may help to know how you are going to use these?
You will need a boost circuit and then should be able to use the LED(s) of choice.Yes, about my application, it is good to mention that i need the LED to be spotted from dozens of meters away, let's say 50 meter +-
I don't mind that there will be 3 LEDs in my housing, one for each color.
This is for indoor use where the light intensity is about 400 LUX.
About the voltage, this is my power source (1.4V) but i can amplify it i guess...
Is that possible?
Thanks a lot for your replies.
What are the properties for Green and Blue?
The lowest possible ones?
Thanks!
I designed and have available for sale a low power LED boost circuit board that runs well from 1.5 volts up to the LED's vf (runs to about 0.8 volts on the low end).You will need a boost circuit and then should be able to use the LED(s) of choice.
If you are using solar cells it is probably better to keep adding them in series to get the voltage high enough to sustain the power level required.First of all, thank you all for your answers.
The problem of using the boost circuit is that there's nothing to do with the fact that P=VI.
If the power (supposed to) stay the same, the current will drop. The power output that I'm using has 325mW.
Currently I'm checking POC of a solar power source that has a 0.5v and 650uA (this is why 325mW). the 650 part is impressive but once i will boost the voltage, the current will drop so it might be a bit more efficient than other solar power sources that i have tested but i will need lots of those in order to make the LED light to dozens of meters.
Please correct me if I'm wrong.
Thank you all.
650uA is 2/3 of a milliamp, if dozens of meters means perhaps 100 feet or more then I would say you probably need a drive current at least 5ma to whatever LED(s) you use and have a focused LED instead of a wide angle one. You could use 7 cells in series for 3.5v and take arrays of such in parallel to increase current output. 9 x 7series would equal about 6ma at 3.5v which should be noticeable 100 feet away if pointed in the right direction.Sure, i can add them serially to get the voltage higher but the current will remain the same.
Let's say i want to get 3v. I will add serially 6 pieces (they are small, it's OK). now i have 3v with current of 650uA. What bright LED will be shown for dozens of meters with those properties?
Thanks.
I don't know your complete problem but I do know they make solar cells quite capable of supplying the power you need.Yes, the math is correct but i cannot add 9 series of those in parallel
It's too much.
In addition, i do need an angle - i cannot point it to 1 direction only.
My problem has no resolution?
Thanks.
BTW the subject of the thread is false. i don't have 1.4v, only 0.5v and 650uA as i wrote previously.