# Looking for IR LED circuit,

Joined Nov 21, 2018
807
Hi,
I known there are IR modules, but I am not handy with that, and I have IR LEDs like the pictures below, where can find a circuit for both IR Emitter and IR Receiver LED?
Thanks

IR LEDs:

modules:

#### BobTPH

Joined Jun 5, 2013
4,769
To do what?

Bob

#### SamR

Joined Mar 19, 2019
4,127
Not knowing exactly what you are looking for, but I often google "XXX circuit" and look under the images tab. It will pull up lots of interesting circuits of the type(XXX) I request. Simply google "IR LED circuits"!

#### Ya’akov

Joined Jan 27, 2019
5,513
Application is very important. You do realize those modules are modulated at 38kHz to avoid problems with ambient IR light? And the receiver board's detector is purpose built for it, not just a simple 5mm detector.

Joined Nov 21, 2018
807

Joined Nov 21, 2018
807
Not knowing exactly what you are looking for, but I often google "XXX circuit" and look under the images tab. It will pull up lots of interesting circuits of the type(XXX) I request. Simply google "IR LED circuits"!
Thank you SamR.

Joined Nov 21, 2018
807
Application is very important. You do realize those modules are modulated at 38kHz to avoid problems with ambient IR light? And the receiver board's detector is purpose built for it, not just a simple 5mm detector.
Thank you Yaakov, you are right, there are many kind of applications. My test shown the 38kHz module can receive IR remoter's signal easy, like TV remoter.

#### BobTPH

Joined Jun 5, 2013
4,769
To do IR signal transfer to control lights kind.
A remote control then? You will need a microcontroller to do that.

Bob

Joined Nov 21, 2018
807
A remote control then? You will need a microcontroller to do that.

Bob
thank you Bob.
I'm using Arduino uno now for testing, I'll use NANO?

#### k1ng 1337

Joined Sep 11, 2020
431
Here is a basic circuit using emitter and photodiode with an analog output. When infared light from D3 shines on D2, D1 will turn on. Replace R2 with a pot for some control. Replace the transitor with a comparator for precise digital control. This circuit is sensitive to ambient light. Using 38khz modules are designed to "listen" on one frequency and so are highly tuned.

Infared remotes send modulated pulses at 38khz so a microcontroller is needed to demodulate the signal. You don't need to modulate though and first experiments can be done with just the 38khz carrier generated from a 555 timer if you have an infared receiver (not module) of the same frequency such as the TSOP4838.

Infared photodiode, receiver and module are each different. A receiver contains a photodiode and a module contains a receiver. Use your phone camera to see if your emitter is working, the light will appear purple and will be plenty bright at 10-20mA.

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#### ErnieM

Joined Apr 24, 2011
8,273
Don't use an IR photo transistor for this. Use an IR receiver module. I intentionally did not give a part number because when you Google that term you will trip over dozens of examples using teh Arduino with links to extremely helpful libraries.

For the transmitter, yeah, IR LEDs are fine.

Joined Nov 21, 2018
807
My Blog entry maybe useful.
Thank you ericgibbs.
especially the disturbance circuit, I am Headache for the noise. what uc you used there?
BTW. do you have simple sending and receiving code for Arduino? I used senddemo kind of code from the Library, always got lot of noise data.
I used the simplest code: How to send + How to receive, the receiver received data very slow.
How to send:
Code:
#include <IRremote.h>
IRsend irsend;

void setup()
{
Serial.begin(9600);
Serial.println("setup");

Serial.print("File   : "), Serial.println(__FILE__);
Serial.print("Date   : "), Serial.println(__DATE__);

}

void loop() {
for (int i = 0; i < 3; i++) {
irsend.sendSony(0xa90, 12); // Sony TV power code
delay(100);

}
}
}

Code:
#include <IRremote.h>

int RECV_PIN = 2;
IRrecv irrecv(RECV_PIN);
decode_results results;

void setup()
{
Serial.begin(115200);
Serial.print("setup!");

Serial.print("File   : "), Serial.println(__FILE__);
Serial.print("Date   : "), Serial.println(__DATE__);

}

void loop() {
if (irrecv.decode(&results)) {
Serial.println(results.value, HEX);
irrecv.resume(); // Receive the next value
}
}

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#### ericgibbs

Joined Jan 29, 2010
15,349
I am using a UNO with a Simple IR Emitter and Non coded IR Receiver. Not a TSOP.
Added the Sketch to show how I am using the Remote control.

I created a virtual keypad using Visual Basic.
E

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Joined Nov 21, 2018
807
I am using a UNO with a Simple IR Emitter and Non coded IR Receiver. Not a TSOP.
Added the Sketch to show how I am using the Remote control.

I created a virtual keypad using Visual Basic.
E
Thank you ericgibbs.
Its a nice example.
do you have clue how to use IR LED as sender, and IR sensor receiver module as a receiver on one or two Arduino that works?

#### ericgibbs

Joined Jan 29, 2010
15,349
hi L,
These two sketch samples may help.

Do you have one of those eBay remote keypads for an IR emitter.?

E

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Joined Nov 21, 2018
807
hi L,
These two sketch samples may help.

Do you have one of those eBay remote keypads for an IR emitter.?

E
Thank you ericgibbs.
I have quite few remoters and also order from EBAY some.
My test with remoters all good.
Now I am looking for is IR LED as a sender not remoter, and received by a IR receiver module.
like these used 1 or 2 Arduino.

#### ericgibbs

Joined Jan 29, 2010
15,349
hi L.
Do you plan to use a simple RX IR receiver diode or the TSOP.?

My projects use a simple IR detector.
E

Update:
BTW: Remote controls are IR Senders/Transmitters , not receivers.

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