Arduino project · Temperature and climate · Easy
Temperature Ring Gauge
The warmer it gets, the more pixels light up, from 20 to 40 degrees C.
What you will learn
- How an LM35 sensor gives 10 mV per degree
- How to map a temperature range to a bar of lights
- How to choose the start and end of a scale
How it works
The sensor voltage is proportional to temperature. The map step says 20 degrees means 0 pixels and 40 degrees means 8 pixels, with the values in between spread evenly.
Try this next
- Add a buzzer for above 38 degrees.
- Move the range to 0 to 100.
- Add an LCD that shows the number.
The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.
Parts: sensors and actuators (tap to show or hide)
Try the inputs (virtual sensors)
Pins (you can change them)
| Part | Arduino pin (change it here) | How to wire it |
|---|
Every wire, one by one
Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.
| # | Colour | From (part and leg) | To |
|---|
Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.
Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.
| # | Item | Qty | Search term | Buy / compare |
|---|
The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.
In the real world
A thermometer on the wall
Move the temperature slider. The mercury in the real thermometer follows.
Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.
- Temperature sensor = the room temperature