IR
Interupt Circuit - In this circuit it is designed so that when something
passes in between the IR Led and the IR phototransistor it causes a positive
signal which can be used to turn on LED's(with appropriate resistor), relays or
anything else you could think of as long as it is under 200mA. For this circuit
to work the LED must be pointing directly at the IR phototransistor. I have not
tested the range that the LED can be away from the phototransistor but my
application for it is an optoswitch for a CNC machine so there is only a small
gap for material to pass in front of the LED. RL is the resistive load to which
you drive with this circuit, if driving an inductive load like a relay or motor
always add a flywheel diode to protect the circuit.
(Click on the image to enlarge it)