The Bosch BMP180 is a high-precision, low-power barometric pressure sensor. It offers a measuring range of 300 to 1100 hPa with an absolute accuracy of down to 0.02 hPa (i.e. to 0.17m altitude near sea level). It's based on piezo-resistive technology for high accuracy, ruggedness and long-term stability.
These sensors come pre-calibrated with the calibration coefficients already stored in ROM. Writing your own code for it requires a bit of mathematics, but there are plenty of examples and libraries already available — if not for the BMP180 specifically, then for its nearly identical predecessor, the BMP085.
This sensor supports a voltage supply between 1.8V and 3.6V DC (regulated 3.3V is ideal). It is designed to be connected directly to a microcontroller via the I2C bus (a.k.a. TWI or the Wire library in Arduino). It comes in an ultra-thin 8-pin ceramic lead-less chip carrier (LCC) package.
For an easy way to experiment with this sensor, see the breadboard-friendly breakout board, SEN-11824.
Note that the BMP180 is sensitive to water, so do not use liquids to clean off excess flux you may have after soldering. Also, the chip is somewhat senstitive to light; best results are achieved when the chip is shielded from ambient light. Of course, it needs access to ambient air, so you should not put it in a completely sealed case.
Barometric Pressure Sensor Features
- Digital two-wire (I2C) interface
- Wide barometric pressure range: 300 to 1100 hPa (approx. altitude range -500 to +9000 meters)
- Flexible supply voltage range: 1.8V to 3.6V
- Ultra-low power consumption: 5 µA @ 1 sample/sec in standard mode
- Accuracy: 0.06 hPa (low-power mode); 0.02 hPa (high-resolution mode)
- I2C data transfer: Up to 3.4 MHz
- Conversion time: 7.5 ms max. in standard mode
- Fully calibrated
- Acts as temperature sensor also, at down to 0.5 °C accuracy
- Low profile and small footprint
Barometric Pressure Sensor Resources