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best way to connect this cheapo IR detector?

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dentaku

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I got this Infrared Emitter & Detector from The Source (Radio Shack in Canada) just for fun **broken link removed**

What's the safe method for connecting the detector when running off of 4AA batteries?
I've found examples of circuits online and they recommend all kinds of different sizes for the resistor.
Maximum voltage and currents
VCEO Collector to emitter: 70V
VECO Emitter to collector: 5V
Ic Collector current: 50mA
Total power dissipation: 150mW
Peak sensitivity wavelength: 850nm
Spectral bandwidth range: 620-980nm
Angle of half sensitivity: +-20deg

This is really cheap stuff with the flat spot on the wrong side on the detector if you follow the directions on the package. but anyway...
I got it to work but it only works well from about 3 centimeters away and I'm curious if it's supposed to work from further?

The IR LED that came in the package is pretty simple to figure out and I used it like any other LED on my breadboard with a 150ohm resistor and it works.
 
Without a complete data sheet, we have to guess somewhat. I think you should design for full saturation of the detector output at 1mA. This implies that the load resistor would be 5.6K ohms. For the emitter, I would first design for 20mA of current, meaning a series resistor on the emitter of 220 to 270 ohms roughly. Your 150 ohms is not a bad choice. These kinds of detectors are intended to work with a carrier frequency of nominally about 40 KHz in order to avoid interference from constant IR sources like your body, nearby lamps and everything else around you. Using a carrier would improve the range. Another thing that would help would be to place a tube on the detector and aim it at the emitter. This improves the directivity of the emitter.
 
If the flat spot on its case is on the wrong side then it is a manufacturing reject and you should return it and get your money back.
Buy the next one from a real electronic parts distributor and it will have a manufacturer's name and a detailed datasheet.
 
It was there and I was curious how they worked. I checked and someone reviewed this product on The Source website and they found the same error.

If the flat spot on its case is on the wrong side then it is a manufacturing reject and you should return it and get your money back.
Buy the next one from a real electronic parts distributor and it will have a manufacturer's name and a detailed datasheet.
 
The Source was RadioShack in Canada for many years. They sold cheap Chinese reject parts at very high prices then their customers did not buy anymore. Then RadioShack got out of Canada and sold the best stores to Circuit City who did the same and went bankrupt.
Bell Canada bought The Source stores and sell expensive cell phones and plans for them. They also sell cheap Chinese reject parts at expensive prices that you bought.
Buy electronic parts from a real electronic parts distributor, not from the cell phone store down the street.
 
Without a complete data sheet, we have to guess somewhat. I think you should design for full saturation of the detector output at 1mA. This implies that the load resistor would be 5.6K ohms. For the emitter, I would first design for 20mA of current, meaning a series resistor on the emitter of 220 to 270 ohms roughly. Your 150 ohms is not a bad choice. These kinds of detectors are intended to work with a carrier frequency of nominally about 40 KHz in order to avoid interference from constant IR sources like your body, nearby lamps and everything else around you. Using a carrier would improve the range. Another thing that would help would be to place a tube on the detector and aim it at the emitter. This improves the directivity of the emitter.

Thanks for the info. I ended up using a 4.7K resistor on the detector and it hasn't melted yet :) I'll have to read about how IR remotes and such work I guess.
I'm very beginner at this stuff so all I did was connect the IR detectors output into the base a 2N2222 and made it switch on an LED.
If I point a regular remote control at it (from a few cm away) the LED blinks and the further away I get the dimmer the LED gets as I was expecting it to ... so it's not dead.

The IR emitter that came in the package specs
Maximum voltage and currents
Reverse Voltage: 5V
Continuous forward current: 150mA
Forward Voltage 1.3V typ., 1.7V max
Radiant power output 13-15mW
Wavelength at peak emission: 950nm
So I guess my 150ohm resistor is OK. I didn't fry it.
 
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