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Infrared detector help? Answered

I have 2 infrared detectors (like the one in picture) with 3 pins and want to make a simple detector to turn power on and off. The reason is that I want to make a line following robot. I only need to be able to put enough power through it to power a relay on or a transistor.
Please help I need to know what all of the pins do and how to use them. Or even better a curket dyagram that turns power on and off by infrared without using micro processors.



Best Answer 7 years ago

"Line following robot diagram"

the first image


shows exactly how to do it.  it has 4 pins on the line portion, 2 for the ir led, and 2 for the detector transistor output.

This particular one is slightly different because it's not only got the ir transistor, but also a 38khz demodulator circuit.
datasheet  explains what each pin does. 
It detects ir light ONLY when its flashing at 38khz, whenever tha happens, the output pin goes from 5v to 0.  This can work for or against you - it means you need your IR source to flash at 38khz, or it will ignore the signal.  To do this you can use a 555 timer or similarly a microcontroller.

Alternately, you can use a different phototransistor that doesn't have a control circuit.

Power and ground connections, and whenever ir light is detected it's output on the out pin.

from http://www.picaxe.com

right, but this isn't just a detector, its got a small computer in it that listens for modulated signal. it won't output anything on the dataline unless you have something that looks like a data source.

Fortunately the Picaxe micro-controller can provide the 30mhz modulated signal and decode the received signal with some very simple programming - Examples available on the site.


7 years ago

you need to program a pic to do it. i am also new to these things but i've controlled my pc using this and my tv remote

these links may help