The DS18B20 is a simple and inexpensive temperature sensor. The sensor operates by an OneWire system, which needs, besides the connections for ground and the supply voltage, only one wire to read the temperature values. By this bus system, it is possible to run multiple sensors which is also described in this tutorial.
Today we build a spirit level with the help of the acceleration sensor ADXL345, an Arduino, a TFT-Display (HY-1.8 SPI) und some other parts.
In this simple circuit, we use a small BH1750FVI sensor on a breakout board and an Arduino to measure the illuminance in lux. Besides the application to measure the illumination of objects in the photography, you can – with an extension of this circuit – also easily make an adapted illumination of rooms or gardens. It is also possible to realize an automatic brightness control for displays.
In the following article we extend the Tiny RTC module with a DS18B20 temperature sensor, which either already exists on the board or we simply add by soldering. This article is an extension of: Time and calendar functions with a real time clock module based on the DS1307 and an Arduino.
In this a bit more extensive project we deal with several factors on the subject of indoor climate. We will measure the temperature, humidity and air pressure, saving maximum and minimum values of our measurements and show it on a TFT display.
On the way to a small weather station we deal today with the air pressure and temperature measurement and use a breakout board for the BMP085 with an I²C interface, and an Arduino of our choice.
Sensors, like the DHT11, are virtually the senses in the world of microcontrollers. With them you can observe, for example, environmental influences, and possibly respond. In this case we deal with the temperature and humidity measurement and therefore we have almost a small weather station.