0

Can you power a 50w LED that by the datasheet needs 30v and 1.5A with less than 30v but 1.5Amps?

Pretty Fly For A Swiss Guy
  • 1
  • You could use a boost converter, but then the LED will get less than 1.5A. The total power (\$V_{LED} \cdot I_{LED}\$) delivered to the LED can't be greater than the input power (\$V_{IN} \cdot I_{IN}\$). – Dave Tweed Feb 08 '16 at 22:22
  • I'm using a step up converter to get 30v from 12v and then deliver those to a current generator for the LED Chip. – Pretty Fly For A Swiss Guy Feb 08 '16 at 22:35

1 Answers1

1

First, anything that operates at 30 V and 1.5 A is not just a LED.

Since we can only guess what your device really is, there is no way to say for sure what it will do if you try to give it less voltage or less current than the spec. Probably it will just get dimmer until at some point it emits no meaningful light at all. That could be at well above 0 V.

The obvious answer is to just try it.

Olin Lathrop
  • 310,974
  • 36
  • 428
  • 915
  • It's a LED chip, it contains 49 1w LEDs. And as far as I know LEDs operate with current, so I thought that maybe I could get a decent result even by having a little less voltage. – Pretty Fly For A Swiss Guy Feb 08 '16 at 22:25
  • 1
    49 LEDs is not just a LED. Decreasing the current will decrease the brightness, but the voltage will only go down a little compared to how much the current goes down. – Olin Lathrop Feb 08 '16 at 22:28
  • What I'm trying to build is a current generator for this LED Chip, and from the example I saw at school for this exact 50w LED chip the voltage needed for this current generator would be 36V, now I can only achieve 30V so the tension on the LED Chip would be lower but I could get the current to be 1.5A anyway – Pretty Fly For A Swiss Guy Feb 08 '16 at 22:32
  • No, you wouldn't get the current to be 1.5A if your supply can only reach 30V. Chances are that LED package of yours only begins to work at 32-33V, and that's just barely. – brhans Feb 08 '16 at 23:55