Have you ever noticed how, on sunny days, the street lamps turn on much earlier than on gray, gloomy days? Streetlights have a built-in smart switch, though this tends to be a very complicated circuit board.

With my endless curiosity in engineering, I decided to simplify the designs of current streetlight circuits. Using some resistors, LED, and circuit gates (NOR Gates), I created a non-inverting Schmitt trigger with hysteresis. This circuit can automatically turn on and off the street light (represented by the LED) according to the environment’s luminosity. The hysteresis provided a luminosity tolerance to allow for a more decisive switch and filter out noise.