I built a house where the rooms really light up! I can turn on the living room, the bedrooms, the porch outside, and even a fireplace that flickers like real fire. I can turn them on one at a time, or all at once.
My house has lots of tiny lights. Something has to tell them all when to turn on and off. So I used a boss to give the orders and helpers to do the heavy work. To make it easy to understand, I think about them like Gru and the Minions from the movie!
The brain of my house is a tiny computer called an Arduino. I call it Gru. Gru is smart and gives all the orders, like “turn on the outside lights!” But Gru is too weak to power all the lights by himself. He needs helpers.
The helpers live inside a little black chip (its real name is a ULN2803A). I think of them as minions. Each minion has one job: turn on one part of the house. When Gru shouts an order, the right minion flips its switch and lets the electricity through. That makes the lights glow!
Electricity flows in a loop, like a race track. It has to go all the way around to work.
An LED is a tiny light. It only works one way, so if you put it in backwards it stays dark! LED is short for Light Emitting Diode.
A transistor is a tiny switch. There are billions of them inside one chip, and each one is smaller than a human hair!
A resistor is like a seatbelt for a light. It stops the light from getting too much power and burning out.
My favorite part is the fireplace. It uses a red light that flickers, so it looks like a real fire in the house. When I press the button, Gru tells the fireplace minion to turn it on!