hi,
i want to make a circuit to LED on detecting any kind of infrared light using infrared detector.
i had made one as deascribed in this link A very simple IR remote control switch for an electrical appliance | Embedded Lab
but i dont want to use CD4017 johnson counter.
is it possible to implement this circuit using transistors or opamp.
Any help will be appreciated.
You can probably connect an LED directly to the output of the IR receiver. Are you planning to use the TSOP1738?
Note: the TSOP1738 is considered "obsolete":
You should use the TSOP34837 or TSOP34137 which have 10 mA outputs capable of lighting an LED.
i can't connect the led directly to the IR receiver because in this case LED will be turned OFFwhen there is no IR is available but i want that LED should keep glowing until IR receiver detects the IR and once the IR falls the receiver the LED should be turned OFF.
I am new to this,
But i think you can power the LED with a larger
Resistor so it turns on with a low light
And connect the LED also to the IR receiver using a diode.
I do not know what you mean by detecting the IR receiver fails.
And if it is possible.
Ah yes...
Basically, the IR light triggers off the transistor, the "trick" to the circuit is C1, it takes a pulsed IR stream and converts it, the transistor merely pulses filling the capacitor, the resistor bleeds
it back to ground, thus the 4017 gets a high on the clock and when it bleeds dry, it's a low again, the 4017 then puts high out to the first pin, increments then it hits reset which starts
the process off again.
The 4017 could easily be replaced, what other IC's do you have? otherwise maybe a transistor based schmitt trigger, i'm pretty sure could easily make the circuit without the 4017.
If you are trying to detect output from an TV type remote then use an IR receiver as suggested earlier. Most IR receivers I have used output +5v (or 3.3V) when no IR is received and 0V when IR is received.
(This of course is when modulated IR is received).
If you want to detect just plain (unmodulated) IR you will likely hit many problems from interference from lights, sun etc. and would require a sophisticated circuit. I presume this is not what you want.
So designing your LED circuit based on whether 5V or 0v is output should be easy.
If you want to incorporate it into the Arduino, then just connect the output of the IR receiver into Pin 2 and write some code to drive the LED (pin 13) based on the value of pin 2.
e.g. digitalWrite(13,digitalRead(2));
Coincidently, we put together a demo of this at last weeks Maker Faire in Dublin, so as we could find out if our IR demos were getting interference from other stands and it worked out very well.
Finally, check out the IRremote library which makes detecting IR codes very easy, with Arduino.
If you place the LED and its series resistor (1K?) between +V and the detector's output pin then the LED will turn on (flicker) when IR signals are present.