High power IR led

Other Hardware General Electronics
1

Hi everyone,
I'd like to drive a high power IR led with Arduino.
The LED is VSLY5850 from Vishay.

I used a 0.5 KΩ resistor at 3.3V but couldn't get it to light up. Is it because of the current needed?
Thanks

2

Please note the data sheet test setup: "IF = 100 mA, tp = 20 ms". Your device is made for PULSED service, not continuous service.

Ohms law will tell you the value for the current limiting resistor, once you decide on the current you want the LED to draw. But you cannot directly connect it to an Arduino pin. You must use a MOSFET to switch the current on/off.

Finally, how were you measuring the IR light from the LED when you determined there was no light?

Paul

3

I need to heat up a Petri dish using infrared radiation.
Surely I'll need an external power supply to provide 100mA. Can I use the LED in a continuous way, without pulsing?

I use a camera to view infrared radiation and a phototransistor for quantitative analysis.

4

"Can I use the LED in a continuous way, without pulsing?"

Only if you can control the internal temperature of the LED junction. The only heat sinking is through the two wore leads.

Paul

5

As to heating a Petri dish even if you could maintain the 100 mA constant your power will only be about 0.165 watt and unless you create an array of IR emitters I can't see how you will get thermal uniformity on your Petri dish. I really can't see using an IR LED giving you any heating effect. You may get by with running the IR LED at half power but I still don't see any heating effect. I assume you have your reasons for wanting IR heating.

Ron

6

A filament (incandescent) light bulb will deliver infrared radiation (as well as visible light). I guess you need between 0.5 to 2 watts but depending on the required temperature and your exact set up. If you don’t want visible light, paint it black or otherwise cover it.

Since the application is heating a Petri dish, google for : usb coffee warmer

7

SeaWalker:
I need to heat up a Petri dish using infrared radiation.
Surely I'll need an external power supply to provide 100mA. Can I use the LED in a continuous way, without pulsing?

I use a camera to view infrared radiation and a phototransistor for quantitative analysis.

Wrong kind of infra red. Heat radiation is around 4--10µm wavelength, this LED is close to visible
light at 0.85µm

8

The idea was to use an array of LEDs.
For the specific LED, being it pulsed and in the wrong frequency range, it is not suited for such application.
Thank you for your replies.