Hi
Anybody know the difference between 850nm LED and 950nm LED being available at Sparkfun?
What I want to know is that which one is more powerful (ie can transmit longer distance).
I want to use it with Uno and control for longer distance.
Regards
It’s not possible to say, as the datasheets provided are woeful (no output power or angle figures are given). I’d suggest using name-brand devices from the likes of Digikey or Mouser if you want proper data.
What’s the waveband of the receiver ? The transmitter’s wavelength needs to be in that band. I think the 950 is closer to most hobbyist receivers.
Thanks for the suggestion.
To answer for Mee_n_Mac: I want to use it with 433MZ RF receiver to control TV, DVD etc.
Actually those IR LED are working at short distance about 5ft. I wanted to control from say,10ft away.
These LED are connected to 5V OUTPUT directly.
Regards
Since you don’t know the frequency of the receivers in your consumer video devices ,you’ll do best to either transmit in both bands or do a comparative test. The internet may also know.
IR LEDs typically have a forward voltage in the 1.2 V range, so you’ll also want a resistor, and you can run 3 of them from 5V without additional current draw. Some IR LEDs can withstand 150 mA .
Thanks for suggestion.
If you are talking about receiver TV, DVD player frequency, I used 38kHz to control and it works.
I connected IR LED directly to output pin so that it can produce more power and can control longer distance, I think.
Principle is same as normal LED connecting to output pin. If I connect directly it is brighter than through 220ohm resistor.
Am I correct?
For control of consumer IR products (TVs, DVDs, etc) the 950 nm LED is the better choice.
As for connecting them directly to some driver … there’s a peak current rating for the LEDs. If you manage to exceed that their lifetime will be cut short. You may also overheat whatever device you’ve connected the LED to and burn that out. The LED below should easily work beyond 10 ft, if driven properly. The driver kit does just that. You can add more LEDs to get even more output. Add 2 or 3 LEDs+resistors in parallel with those shown in the schematic or you can add 1 LED in series with the one shown and reduce the resistor to something near 20 ohms. My guess is that a single LED should be sufficient though.