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Electronics => Electronics => Topic started by: evilknight007 on October 26, 2007, 08:52:31 AM

Title: TSOP circuit
Post by: evilknight007 on October 26, 2007, 08:52:31 AM

Hi Ppl..
Can anyone give me a circuit for TSOP based IR proximity sensor circuit .
I have been trying out some circuits based on TSOP based sensors. But none seems to be working.  :(  ???

i hv given a link of the circuit i hv been trying out . whats wrong in it . .The data sheet of TSOP says tat it is necessary to generate a short bursts of modulated wave . But the circuit seems to give only continuous modulated wave .Is that what is missing out in here .
http://www.triindia.co.in/resources_images/CircuitPool/TSOP%20based%20obstacle.jpg (http://www.triindia.co.in/resources_images/CircuitPool/TSOP%20based%20obstacle.jpg)
Thanks .

Title: Re: TSOP circuit
Post by: Ro-Bot-X on October 26, 2007, 09:39:22 AM

TSOP IR receivers will filter out as noise any modulated signal that is continous for more than a few miliseconds. So all you need to do is connect a microcontroller to the R pin on the 555 IC. This pin should be connected to Vcc through a 100k resistor, not directly. Basically you toggle the output pin from the microcontroller from Low to High and back to Low, for a few miliseconds. Instead of the microcontroller you could use a second 555 tuned for a low frequency that will turn on and off the first one.

If you use Panasonic PNA4602 (38kHz) you don't have this problem.

Title: Re: TSOP circuit
Post by: hgordon on October 26, 2007, 10:25:53 AM

Here's a schematic that uses the TSOP 1736 receiver and TSAL 6200 emitter -
    http://www.surveyor.com/images/srv-schematic.jpg

You'll find firmware source code to modulate the emitter in utils.c
    http://www.surveyor.com/srvdownload/srv-053007.zip

Title: Re: TSOP circuit
Post by: evilknight007 on November 01, 2007, 12:46:48 PM

thank u guys .. will let u know if it works .thanks again