TSOP1738 infrared sensor

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electroboy

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hello.. i want to know about TSOP1738 infrared sensor.. how it works?, what output it will produce when it detects ir light? etc... please help me. i have seen the datasheet but i cant understand clearly.. also please suggest me whether it is good for some basic applications like proximity detector , people counter model etc.. thanks in advance..
 

Application : works great in all applications u mentioned.... but it is preferably used in applications which have problem with Ambient light.....
as TSOP17xx are not affected by ambient light....!!


TSOP17xx
These are optical recievers which responds to IR light switching at an frequency of xx( described by last 2 digits of IC Name)
so TSOP1738 responds to the IR switching at a frequency of 38kH.

Pins
**broken link removed**
it's very simple to use....
pin 1 => Ground
Pin 2=> +5V
Pin 3 => it's the output.....which gives +5V or 0V depending upon the IR wave is received or not....
give 0V when receiving signal
and gives +5V when signal is not available....


here is how u should connect it to the circuit....



Hope that helps.... ;-)
All the Best..!!

---------- Post added at 08:16 ---------- Previous post was at 08:14 ----------

also at optical transmitter u can use IR led at the output of an 555Timer(in Astable Mode)

Regards...

Nikhil.... ;-)
 
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TSOP1738 detects only 38KHz modulated IR light(ideally) . It Means, while 38KHz modulated IR signal falls over the TSOP1738 its output will be LOW. (active low device) and all other time, its O/P will be high....
So u can send a serial data by using ASK (carrier frequency 38KHz) where the ASK o/p is connected to an IR LED and the data could be received at the TSOP1738 o/p kept at a distance.
The same thing is happening in ur TV remote system...

As an experiment, u can design an ASTABLE MV at frequency 38KHz.
some useful tips :
>Connect a capacitor(say 100uF) in parallel to supply to MV(multivibrator), close to MV circuit..
>Use a 100 ohms resistor in between the supply and tsop +ve .
>Must connect a decoupling capacitor(say 100uF) in parallel to TSOP supply pins, very close to THE PINS....(This prevents 38KHz noise from multivibrator which could enter the TSOP through its supply leads.:idea:..and thus prevents undesirable o/p at TSOP....) This point is very important if u use same power suppply for TSOP and Multivibrator

Then connect an IR led at o/p of MV .(connect a proper resistor in series with IR led if the Vcc to MV is high)


U can see IR led glowing just by watching it through ur mobile digital camera...
Now i think u can make proximity sensor, people counter etc by ur own....;-)
 
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wow..thank you very very much sir(s).. what a great forum !!!..But I cant view any images .. it comes domain unregistered.....please help me in another doubt also .. in datasheet it is mentioned that the burst length should be 10 cycles or longer.. please explain me what is burst and burst length..?
 
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Look, just think what are we doing....

Burst : It's the IR Light coming on the TSOP without any break....

Burst Length for detection : 10 cycles per burst or longer => this means there should be atleast 10 cycles of IR Light going ON and OFF in a burst...

here look at this pic....


i am sure about this to 99%, but want a senior guy to check...

if u still have a problem....feel free to ask....

Nikhil
 
Thank you very much... This is greatly helpful...
 

doing the same project for MOBOT collision sensor...

very nice thread...
 

Hello guys,. i too have a doubt in this same topic..

I have bought an IR led which is in quite black color,.. Was that the one which is soo called IR led..???

I connected the black color led to a 9 V batter with 1k of resistor series in between the source and IR led...

Then, i switched on my Digital camera of my phone,.. but i cant see the GLOWING IR LED.. :roll:
(NOTE: i checked the same procedure with my tv remote controller and it worked successfully)..
Please suggest me any help..

Thanks in advance.. :smile:
 


almost all IR LED's i have used showed up in digital camera....

and your digital camera detects IR of Remote.....this means that ur camera also captures IR range of EM waves.....

so to me it seems that your IR LED is not working correctly.....

- Make sure that the polarity of LED is correct.(Long Leg of LED is connected to +ve Terminal...)
- Try different IR LED....

Tell me what happened....
 
One point, as i know if you send continous pulses to IR receiver, cct inside the TSOP17xx is saturated. And cannot generate output anymore. So as seen on the diagrams there should be some time gaps (off cycles).
 

guyz how can i control upto 8 devices by using a single tsop as there is 1 centre frequency for a single tsop ? please reply any 1
 

guyz how can i control upto 8 devices by using a single tsop as there is 1 centre frequency for a single tsop ? please reply any 1
A TSOP1738 is used as the IR receiver for many TVs. It is not used for old stupid single-function Morse Code, instead it receives modern complicated programmed digital CODE that has the address of maybe 30 or 40 functions then a digit that says if the function should turn on or turn off or go to a certain level.
 

Hello everyone..
Can i count the number of people entering and leaving a room using the TSOP ir sensor?
Please help me out with an idea.
 

To count people entering and leaving a room you need a separate entrance and separate exit so people coming and going do not cross each other.

A TSOP1738 is too complicated since you must modulate the IR carrier at 38kHz and insert bursts of data pulses and pauses between bursts as shown on its datasheet.
Instead, a simple steady IR or laser beam can be interrupted by a person and the detector is a simple photo-transistor.

- - - Updated - - -

To count people entering and leaving a room you need a separate entrance and separate exit so people coming and going do not cross each other.

A TSOP1738 is too complicated since you must modulate the IR carrier at 38kHz and insert bursts of data pulses and pauses between bursts as shown on its datasheet.
Instead, a simple steady IR or laser beam can be interrupted by a person and the detector is a simple photo-transistor.
 

Hello Audioguru and sarath ksk,

To count people entering and leaving a room you need a separate entrance and separate exit so people coming and going do not cross each other.

that is not nessesary. In the 1970 and 1980 there where so much circuits for counting people at a door or to switch the light automaticly.

I must only look in my circuit archieve to find and redraw the circuits. I look for it during the day.

Regards

Rainer
 

hi nikhil,

TSOP 1738 is only works on 38 khz or it will works on any other frequency?
one more is, if i want to increase the transmitter and receiver distance means then what should i do?

kindly help me

regards,

vignesh...
 

To increase the distance for IR communication then you can use an IR LED that you can BLAST 1A current pulses, like the IR LEDs used in TV remote controls.
You can also focus the IR beam so that its power is concentrated.

IR language translation communications in large banquet halls use many IR high power LEDs in an array.
 

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