Altitude Pressure EXperimental (APEX) Sensor Board

The design makes use of the following Freescale products: MPL115A2, MPXM2102A, MPXV5004G pressure sensors with an MMA7361L accelerometer. It also utilizes Freescale's Flexis MC9S08JM60 8-bit microcontroller. The sensors with analog outputs are sampled via the JM60 microcontroller's 12-bit ADC. The exception is the MPXM2102A absolute pressure sensor. This is used for altitude so it requires a high resolution sampling. It passes through an instrumentation amplifier and then is interfaced via an external 24-bit ADC chipset before communication via SPI to the JM60 MCU. The JM60 interfaces with the LCD screen and processes inputs by the user for the output display .

The APEX is useful in a wide variety of applications including altimeter, barometer, barometer alarm, weather station, water level, water level alarm, tilt, freefall, and temperature sensing.