The flight computer I am developing for my next rocket uses an atmospheric pressure sensor to calculate the flight altitude. I chose to use a Motorola MPX4100 sensor, since it is readily available through Conrad.be. It outputs a voltage proportional to the pressure; 0,3 V at 20 kPa and 4,9 V at 105 kPa.
The MPX4100A sensor is an SMD part (SOP case), so I needed a breakout board to be able to breadboard it. Below are the circuit diagram and the PCB layout in Eagle format.
I have recently started using Eagle to make my electronics projects, and i works so great that I finally got round to making a few boards I need very often. One of them was a power supply that plugs into the power rails of the bread board I use for prototyping my circuit.
The power supply can be fed from a wall wart, and supplies 5V and 12V to the breadboard’s power rails. It uses a pair of 7805 and 7812 IC’s for regulation.