These are the only 5 pins we are going to connect. The other pins which control strobe capability and balance will be left unconnected; we will not use these features.
For our circuit, we will connect a potentiometer to the noninverting terminal. This will allow us to adjust the potentiometer to set a reference voltage level.
We will then connect a voltage divider circuit, consisting of a fixed resistor and a photoresistor, to the inverting terminal of the comparator.
How the circuit works is when the photoresistor is exposed to bright light, it has very low resistance. Thus, very little voltage falls across it (ohm's law tells us this). Therefore, the voltage at the inverting terminal will be less than at the noninverting terminal. So the load connected to the output will be off. However, when the photoresistor is exposed to darkness, its resistance increases dramatically, and so will the voltage that falls across it. Thus, the voltage the inverting terminal will now be greater than at the noninverting terminal, and so the load connected to the output will be turned on.
Thus, our circuit will function as a night light circuit. It will turn on an LED during dark conditions.