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DESCRIPTION

This pressure sensor from Freescale is a great low-cost sensing solution for

measuring barometric pressure. At 1.5 hPa resolution, it's not as precise as our

favorite pressure sensor, the BMP085, which has up to 0.03 hPa resolution so we

don't suggest it as a precision altimeter. However, it's great for basic barometric

pressure sensing. The sensor is soldered onto a PCB with 10K pull-up resistors on

the I2C pins.

This chip is good for use with power and logic voltages ranging from 2.4V to 5.5V

so you can use it with your 3V or 5V microcontroller. There's a basic temperature

sensor inside but there's no specifications in the datasheet so we're not sure how

accurate it is.

This chip looks and sounds a whole lot like the MPL3115A2 but this is the less

precise version, best for barometric sensing only

Using the sensor is easy. For example, if you're using an Arduino, simply connect

the VDD pin to the 5V voltage pin, GND to ground, SCL to I2C Clock (Analog 5 on

an UNO) and SDA to I2C Data (Analog 4 on an UNO). Then download our MPL115A2

Arduino library and example code for temperature, pressure and basic altitude

calculation. Install the library, and load the example sketch. Immediately you'll have

the temperature, pressure and altitude data printed in the serial console.

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7/23/2015

http://www.adafruit.com/products/992