BME280

Bosch Sensortec BME280 Integrated Environmental Unit GENERAL DESCRIPTION The BME280 is an integrated environmental sensor developed specifically for mobile applications where size and low power consumption are key design constraints. The unit combines individual high linearity, and high accuracy sensors for pressure, humidity and temperature in an 8-pin metal-lid 2.5 x 2.5 x 0.93 mm3 LGA package. The BME280 designed for low current consumption (3.6 µA @1Hz), long term stability, and high EMC robustness. The humidity sensor features an extremely fast response time which supports performance requirements for emerging applications such as: context awareness, and high accuracy over a wide temperature range. The pressure sensor is an absolute barometric pressure sensor which features exceptionally high accuracy and resolution at very low noise. The integrated temperature sensor has been optimized for very low noise and high resolution. It is primarily used for temperature compensation of the pressure and humidity sensors, and can also be used for estimating ambient temperature. The BME280 supports a full suite of operating modes which provides the flexibility to optimize the device for power consumption, resolution, and filter performance. BME280 TARGET APPLICATIONS  Context awareness, e.g. skin detection, room change detection  Fitness monitoring/well-being ‒ Warning regarding dryness or high temperatures ‒ Measurement of volume and air flow  Home automation control ‒ Control heating, ventilation, air conditioning (HVAC)  Internet of things  GPS enhancement (e.g. time-to-first-fix improvement, dead reckoning, slope detection)  Indoor navigation (change of floor detection, elevator detection)  Outdoor navigation, leisure and sports applications  Weather forecast  Vertical velocity indication (rise/sink speed) TECHNICAL SPECIFICATIONS BME280 (preliminary) Technical data Package dimensions 8-Pin LGA with metal 2.5 x 2.5 x 0.93 mm³ Operation range (full accuracy) Pressure: 300 ... 1100 hPa Temperature: -40 … +85 °C Supply voltage VDDIO Supply voltage VDD 1.2 ... 3.6  V 1.71 ... 3.6 V Interface I²C and SPI Average current consumption (typ.) (1Hz data refresh rate) 1.8 μA @ 1 Hz (H, T) 2.8 μA @ 1 Hz (P, T) 3.6 μA @ 1 Hz (H, P, T) T = temperature Average current consumption in sleep mode 0.1 µA Humidity sensor Response time (τ63%) Accuracy tolerance Hysteresis Pressure sensor RMS Noise Sensitivity Error Temperature coefficient offset 1s ±3 % relative humidity ≤2 % relative humidity 0.2 Pa (equiv. to 1.7 cm) ±0.25 % (equiv. to 1 m at 400 m height change) ±1.5 Pa/K (equiv. to ±12.6 cm at 1 °C temperature change) RoHS compliant, halogen-free, MSL1 Bosch Sensortec | BME280 2|2 SENSOR OPERATION The BME280 supports I2C and SPI (3-wire/4-wire) digital, serial interfaces. The sensor can be operated in three power modes: Sleep mode, normal mode and the forced mode. In normal mode the sensor automatically cycles between a measurement and a standby period. This mode is recommended when using BME280 built-in IIR filter when short-term disturbances (e.g. blowing into the sensor) need to be filtered. In forced mode, the sensor performs a single measurement on request and returns to sleep mode afterwards. This mode is recommended for applications that require a low sampling rate or host-based synchronization. In order to tailor data rate, noise, response time and current consumption to the needs of the user, a variety of oversampling modes, filter modes and data rates can be selected. In combination with several short term disturbance filter settings, the sensor can be programmed in a very flexible way in order to adapt to application and power management requirements. To simplify the design-in phase, default settings optimized for several example use-cases such as weather monitoring, elevator/stair case detection, drop detection or indoor-navigation are provided. Pin configuration (bottom view) TECHNICAL SPECIFICATIONS Pin configuratio Pin Name n 1 GND 2 3 4 5 6 7 8 CSB SDI SCK SDO VDDIO GND VDD SOFTWARE Function Ground Chip select Serial data input Serial clock input Serial data output Digital/Interface supply Ground Analog supply TECHNOLOGY AND SPECIFICATION Emerging applications such as indoor navigation, home automation control, personalized weather stations, and innovative sport and fitness tools require a pressure sensor with high relative accuracy and a low TCO, in combination with fast response, high accuracy of relative humidity and ambient temperature measurements. The BME280 is perfectly suitable for such applications as the device features excellent relative accuracy of ±0.12 hPa (equivalent to ±1 m difference in altitude), and an offset temperature coefficient (TCO) of only 1.5 Pa/K (equivalent to 12.6 cm/K). The Altitude Content Provider ACP2.0 software is available as a software package for the BME280 which calculates the altitude with best possible accuracy. The ACP2.0 uses the sea level pressure to calculate the altitude, compensating for the nonsphericallicity of the earth by geoid correction, and compares its altitude with current altitude given by the GPS module, if available. SYSTEM COMPATIBILITY The BME280 has been designed for best possible fit into modern mobile consumer electronics devices. Besides the ultrasmall footprint and very low power consumption, the BME280 has very wide ranges for VDD and VDDIO supply voltages. Bosch is the world market leader in MEMS sensors. The BME280 from Bosch Sensortec combines extensive experience with reliability for consumer applications. Bosch Sensortec is a subsidiary of Bosch that focuses on micromechanical components for the non-automotive markets. Headquarters Bosch Sensortec GmbH Gerhard-Kindler-Strasse 9 72770 Reutlingen · Germany Telephone +49 7121 3535 900 Fax +49 7121 3535 909 www.bosch-sensortec.com Data & Specification are preliminary and subject to change without notice | | Bosch Sensortec GmbH reserves all rights in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbols are registered trademarks of Robert Bosch GmbH, Germany.