Read pressure with the MPL115A2 sensor and MEMs technology
It's not our first first barometric sensor, they are very useful to create your own meteo station or measure the altitude.
This pressure sensor is special because it have a tubular mecanical connection to plug pipe for measuring pressure with this sensor. So, with le MPL115A2, you can measure the pressure into a closed environment (vaccum chamber or pressurized environment).
The MPL115A2 can measure absolute pressure from 0 PSI to 25 PSI (so between 0 to 1723 millibar).
To help in comparison of this pressure range with real world:
- The atmospheric pressure on earth is around 1025 millibar (so 14.8 PSI)
- The water network distribution at kitchen tap have a pressure of 3 to 5 bar (3000 to 5000 millibar, 43.5 to 72.5 PSI).
- The bottle of Champagne rise its internal pressure due to fermentation to 4800 - 5500 millibar (70 - 80 PSI). The Cola bottle, as many soda bottle, is pressurized to 1700 - 2400 millibar (25 à 35 PSI).
Most of pressure sensor are usually use a analog output to communicates measurement. This sensor is, once again different, using a I2C bus to communicates data. This sensor is easy to interface with anasy microcontroleur by using only 2 wires to transmit data.
This component is made of a sensor part immerge inside a silicon based gel plus an 24 bits ADC converter (Analog to digital) having pre-calibration and compensation.
The mechanical tube is made of stainless steel having 3.7mm long and 2.5mm diametre.
The component is assembled on a breakout board with 3.3V power regulation and level shifting so you can use it with any kind of microcontroller or microcomputer, from an Arduino compatible to Raspberry Pi
Pour finir, Adafruit propose des code d'exemple pour Arduino, Python/CircuitPython.
Just for the pleasure of knowledge:
- Do you know that a 0.5L Cola bottle can resist up to 14 Bar of pressure? See this experiment on YouTube.
- Cooking food in a pressure cooker brings the pressure to 1 bar above standard atmospheric pressure. As the result of higher pressure, the water boils around 120 ° C and it is also the temperature of the steam. This method is effective in destroying more bacteria.
Applications for the MPL115A2
Beside the obvious application for vaccum chamber or pressurized environment, such sensor is quite handy to create Sip-and-Puff (wikipedia) interface to create object that can be controlled by sucking or blow into a straw.
For each order, you will receive the MPL115A2 assembled on the breakout board with all the necessary components. The board is tested by Adafruit before shipping.
The board is shipped without silicon tube (you must purchase it seperately, we can propose this silicon tube product with an internal diameter of 2mm).