hello
I have a small project which is need to negative switching. Is negative switching possible with IR sensor ?
IR Led with photo transistor circuit readily available .
A phototransistor works similar to an NPN. The obvious circuit to build is a common-emitter amplifier. It inverts the signal (light shining). Which is to say it provides a path to ground. Is that the kind of switching your question is about?
This is good for you. But what can we gain from this information? ...since we can't see the circuit...
Rarely that 1 and 1/2 lines of text can precisely describe a problem in a forum.
What about using a sheet of paper, a pencil and doing some drawings. Block diagram, a schematic, a signals...