Hi,
I made the attached circuit to make an automatic soap dispenser ... it works well except that sometimes when the timed out ends and you take your hand from under the IR sensor the timed out is reactivated ...

some advice? thank you.

 

hi tnn,
Look at page #3, Note the required pulse train.
Your 38kHz is continuous, this may cause a problem.
E
Update:

 

but it doesn't always happen ... 10 times example it happens 2/3 times ...

 

What if I add a 1µF electrolytic capacitor between pin3 of PH1 and gnd?

 

you take your hand from under the IR sensor the timed out is reactivated

Is it flashing IR between your fingers to restart?