Hi everyone.
I am trying to re-construct a VERY SIMPLE circuit that turns on a lamp once darkness is detected. The idea came from a small night light that plugs into an AC outlet. There is a small photo sensor in the unit that turns on the small 4 Watt night light when darkness is detected and turns it off when there is light in the room. The beauty of this circuit is its simplicity, and the fact that it does not require external power to drive a relay or some other components. It takes the power right from the AC outlet.
There is one component that I cannot identify, I was wondering if anyone can give me some help?
Here is a quick drawing of the circuit found inside the night light. I have also attached a photo of the Unknown IC. The IC comes in a TO92 package. I am sure it is not an NPN or PNP.
As it is now, the circuit does not work. The light stays on all the time. I suspect that the unknown IC is not functioning properly.
The photo resistor measures roughly 130 ohms in the light and around 2K ohms when the photo resistor is covered up.