View Full Version : tsop doubt

05-29-2009, 09:58 PM
hi friends,
i wanted to check whether my TSOP works or not , so i did all neccessary connections and tested with a tv remote .
without any signal from remote i got 5.40 volts and with the remote signal i got 4.80 volts output . i read that it gives active low when it detects 38khz signal but 4.80 volts doesn't seem to be active low to me or is it ??
is my tsop working right??
and iam somoking up my ir led pretty soon whats the resistor value i should put but still get powerful signals from it??

05-29-2009, 10:26 PM
Just add a led to the output, you will get to know if it blinks. Also there have been so many posts regarding TSOP. Should have searched the forum first

05-30-2009, 07:38 AM
Its not surprising that its showing 4.8V.
The output from the TSOP is in the form of fast pulses when a TV remote is pointed at it. Hence , the meter will show the average voltage , which might be around 4.8V.

As shobhitkukreti said , put an LED and then check. If the LED appears to be blinking fast , then its working.

And BTW , the recommended voltage for the TSOP is 4.5-5.5V. Why are you pushing the TSOP to its limits by using 5.5V? Why dont you use 5v which is simple to obtain from a 7805?

05-30-2009, 01:59 PM
ok i get it ,
thanks for the update !!

06-11-2009, 10:34 PM
you can also test by this circuit


08-30-2009, 06:09 PM
tsop1736 will also perform same :)