Arduino thermometer with an alarm: LM35, LCD and buzzer
Open in the lab ▸Make my own copy
An LM35 puts out 10 mV for every °C, so 380 mV is 38 °C. The Arduino reads it, shows the temperature on a 16×2 I²C LCD and sounds a buzzer above 35 °C: a server-room, incubator or aquarium alarm in five parts. Click the LM35 and change the temperature. Open it and press Run: the sketch is inside the board (click the board, then Code). Every part, pin and resistor matches what you would build on a real breadboard; the guided build of the same name has the test sheet and hidden faults.
What is on the bench
5 parts, 10 wires, with a sketch (the program runs in the lab). Boards: Arduino Uno R3.
| Arduino Uno R3 | 1 |
|---|---|
| USB charger / port | 1 |
| LM35 temperature sensor | 1 |
| Active buzzer | 1 |
| I2C LCD | 1 |
Put it on your page
The project runs live inside the frame: readers can press buttons, turn knobs and read the meters.
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Link
https://zencircuitlab.com/p/zclctemp
Published by its author under the lab's community terms: it may be opened, copied and changed by anyone. Simulation results are for learning; check a real build against the parts' datasheets.