Data sheet BMP280 Digital Pressure Sensor Bosch Sensortec BOSCH Invented for life BMP280: Data sheet Document revision 1.14 Document release date May 5th, 2015 Document number BST-BMP280-DS001-11 Technical reference code(s) 0273 300 416 Notes Data in this document are subject to change without notice. Product photos and pictures are for illustration purposes only and may differ from the real product's appearance. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 2 BMP280 Digital Pressure Sensor Key parameters Pressure range Package Relative accuracy (950 ... 1050hPa @25°C) Absolute accuracy (950 ...1050 hPa, 0 ...+40 °C) 300 ... 1100 hPa (equiv. to +9000...-500 m above/below sea level] 8-pin LGA metal-lid Footprint: 2.0 * 2.5 mm2, height: 0.95 mm ±0.12 hPa, equiv. to ±1 m typ. ±1 hPa Temperature coefficient offset 1.5 Pa/K, equiv. to 12.6 cm/K (25 ... 40°C @900hPa) Digital interfaces Current consumption Temperature range RoHS compliant, halogen-free MSL 1 PC (up to 3.4 MHz) SPI (3 and 4 wire, up to 10 MHz) 2.7uA @ 1 Hz sampling rate -40 ... +85 °C Typical applications • Enhancement of GPS navigation (e.g. time-to-first-fix improvement, dead-reckoning, slope detection) • Indoor navigation (floor detection, elevator detection) • Outdoor navigation, leisure and sports applications • Weather forecast • Health care applications (e.g. spirometry) • Vertical velocity indication (e.g. rise/sink speed) Target devices • Handsets such as mobile phones, tablet PCs, GPS devices • Navigation systems • Portable health care devices • Home weather stations • Flying toys • Watches Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 3 General Description Robert Bosch is the world market leader for pressure sensors in automotive and consumer applications. Bosch's proprietary APSM (Advanced Porous Silicon Membrane) MEMS manufacturing process is fully CMOS compatible and allows a hermetic sealing of the cavity in an all silicon process. The BMP280 is based on Bosch's proven Piezo-resistive pressure sensor technology featuring high EMC robustness, high accuracy and linearity and long term stability. The BMP280 is an absolute barometric pressure sensor especially designed for mobile applications. The sensor module is housed in an extremely compact 8-pin metal-lid LGA package with a footprint of only 2.0 * 2.5 mm2 and 0.95 mm package height. Its small dimensions and its low power consumption of 2.7 uA @lHz allow the implementation in battery driven devices such as mobile phones, GPS modules or watches. As the successor to the widely adopted BMP180, the BMP280 delivers high performance in all applications that require precise pressure measurement. The BMP280 operates at lower noise, supports new filter modes and an SPI interface within a footprint 63% smaller than the BMP180. The emerging applications of in-door navigation, health care as well as GPS refinement require a high relative accuracy and a low TCO at the same time. BMP180 and BMP280 are perfectly suitable for applications like floor detection since both sensors feature excellent relative accuracy is ±0.12 hPa, which is equivalent to ±1 m difference in altitude. The very low offset temperature coefficient (TCO) of 1.5 Pa/K translates to a temperature drift of only 12.6 cm/K. Please contact your regional Bosch Sensortec partner for more information about software packages enhancing the calculation of the altitude given by the BMP280 pressure reading. Table 1: Comparison between BMP180 and BMP280 Parameter BMP180 ■ BMP280 Footprint 3.6 x 3.8 mm 2.0 x 2.5 mm Minimum VDD 1.80 V 1.71 V Minimum VDD|0 1.62 V 1.20 V Current consumption @3 Pa RMS noise 12 uA 2.7 uA RMS Noise 3 Pa 1.3 Pa Pressure resolution 1 Pa 0.16 Pa Temperature resolution 0.1°C 0.01°C Interfaces l2C PC & SPI (3 and 4 wire, mode '00' and '11') Measurement modes Only P or T, forced P&T, forced or periodic Measurement rate up to 120 Hz up to 157 Hz Filter options None Five bandwidths Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 4 Index of Contents 1. SPECIFICATION........................................................................................................................7 2. ABSOLUTE MAXIMUM RATINGS............................................................................................9 3. FUNCTIONAL DESCRIPTION.................................................................................................10 3.1 Block diagram...............................................................................................................11 3.2 Power management.......................................................................................................11 3.3 Measurement flow.......................................................................................................11 3.3.1 Pressure measurement...........................................................................................................12 3.3.2 Temperature measurement.....................................................................................................13 3.3.3 MR filter....................................................................................................................................13 3.4 Filter selection............................................................................................................14 3.5 Noise..............................................................................................................................15 3.6 Power modes.................................................................................................................15 3.6.1 Sleep mode................................................................................................................................16 3.6.2 Forced mode.............................................................................................................................16 3.6.3 Normal mode.............................................................................................................................16 3.6.4 Mode transition diagram.........................................................................................................17 3.7 Current consumption...................................................................................................18 3.8 Measurement timings....................................................................................................18 3.8.1 Measurement time....................................................................................................................18 3.8.2 Measurement rate in normal mode.........................................................................................19 3.9 Data readout................................................................................................................19 3.10 Data register shadowing...........................................................................................20 3.11 Output compensation.................................................................................................20 3.11.1 Computational requirements...............................................................................................20 3.11.2 Trimming parameter readout................................................................................................21 3.11.3 Compensation formula..........................................................................................................21 3.12 Calculating pressure and temperature...................................................................22 4. GLOBAL MEMORY MAP AND REGISTER DESCRIPTION..................................................24 4.1 General remarks..........................................................................................................24 4.2 Memory map...................................................................................................................24 4.3 Register description....................................................................................................24 4.3.1 Register OxDO "id"....................................................................................................................24 4.3.2 Register OxEO "reset"..............................................................................................................24 4.3.3 Register 0xF3 "status"............................................................................................................25 4.3.4 Register 0xF4 "ctrl_meas"......................................................................................................25 4.3.5 Register 0xF5 "config"............................................................................................................26 4.3.6 Register 0xF7...0xF9 "press"Cmsb, _lsb, _xlsb)..................................................................26 4.3.7 Register 0xFA...0xFC "temp" (_msb, _lsb, _xlsb)...................................................................27 Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 5 5. DIGITAL INTERFACES............................................................................................................28 5.1 Interface selection......................................................................................................28 5.2 l2C Interface..................................................................................................................28 5.2.1 l2C write....................................................................................................................................29 5.2.2 l2cread.....................................................................................................................................29 5.3 SPI interface.................................................................................................................30 5.3.1 SPI write...................................................................................................................................31 5.3.2 SPI read....................................................................................................................................31 5.4 Interface parameter specification.............................................................................32 5.4.1 General interface parameters...............................................................................................32 5.4.2 l2C timings.................................................................................................................................32 5.4.3 SPI timings................................................................................................................................33 6. PIN-OUT AND CONNECTION DIAGRAM...............................................................................35 6.1 Pin-out...........................................................................................................................35 6.2 Connection diagram 4-wire SPI...................................................................................36 6.3 Connection diagram 3-wire SPI...................................................................................37 6.4 Connection diagram l2C................................................................................................38 7. PACKAGE, REEL AND ENVIRONMENT................................................................................39 7.1 Outline dimensions.......................................................................................................39 7.2 Landing pattern recommendation...............................................................................40 7.3 Marking..........................................................................................................................41 7.3.1 Mass production devices........................................................................................................41 7.3.2 Engineering samples................................................................................................................41 7.4 Soldering guidelines....................................................................................................42 7.5 Tape and reel specification.........................................................................................43 7.5.1 Dimensions................................................................................................................................43 7.5.2 Orientation within the reel.....................................................................................................43 7.6 Mounting and assembly recommendations.................................................................44 7.7 Environmental safety..................................................................................................44 7.7.1 RoHS.........................................................................................................................................44 7.7.2 Halogen content.....................................................................................................................44 7.7.3 Internal package structure...................................................................................................44 8. APPENDIX 1: COMPUTATION FORMULAE FOR 32 BIT SYSTEMS..................................44 8.1 Compensation formula in floating point....................................................................44 8.2 Compensation formula in 32 bit fixed point................................................................45 9. LEGAL DISCLAIMER...............................................................................................................47 9.1 Engineering samples....................................................................................................47 BST-BMP280-DS001-11 I Revision 1.14 I May 2015 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 6 9.2 Product use............................... 9.3 Application examples and hints 47 47 10. DOCUMENT HISTORY AND MODIFICATION.....................................................................48 Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 7 1. Specification If not stated otherwise, All values are valid over the full voltage range All minimum/maximum values are given for the full accuracy temperature range Minimum/maximum values of drifts, offsets and temperature coefficients are ±3a values over lifetime Typical values of currents and state machine timings are determined at 25 °C Minimum/maximum values of currents are determined using corner lots over complete temperature range • Minimum/maximum values of state machine timings are determined using corner lots over 0...+65 °C temperature range The specification tables are split into pressure and temperature part of BMP280 Table 2: Parameter specification Parameter Symbol Condition Min Typ Max Units Operating temperature TA operational -40 25 +85 °C range full accuracy 0 +65 Operating pressure range P full accuracy 300 1100 hPa Sensor supply voltage VDD ripple max. 50mVpp 1.71 1.8 3.6 V Interface supply voltage Vddio 1.2 1.8 3.6 V 1 Hz forced mode, Supply current Idd.lp pressure and temperature, lowest power 2.8 4.2 uA Peak current Ipeak during pressure measurement 720 1120 uA Current at temperature measurement Iddt 325 Sleep current1 Iddsl 25 °C 0.1 0.3 uA Standby current (inactive period of normal mode)2 Iddsb 25 °C 0.2 0.5 uA Relative accuracy pressure VDD = 3.3V A , 700 ... 900hPa ±0.12 hPa Mrel 25 ... 40 °C ±1.0 m Typical value at VDD = VDDIO = 1.8 V, maximal value at VDD = VDDIO = 3.6 V. Typical value at VDD = VDDIO = 1.8 V, maximal value at VDD = VDDIO = 3.6 V. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 8 Offset temperature TCO 900hPa ±1.5 Pa/K coefficient 25 ... 40 °C 12.6 cm/K Absolute accuracy APex, 300 ... 1100 hPa -20 ... 0 °C ±1.7 hPa pressure APfuii 300... 1100 hPa 0 ... 65 °C ±1.0 hPa Resolution of output data in ultra high resolution mode Rp Pressure 0.0016 hPa RT Temperature 0.01 °C Vp.full Full bandwidth, ultra high resolution See chapter 3.5 ,3 Pa Noise in pressure 11 cm VPifi|tered Lowest bandwidth, 0.2 Pa ultra high resolution See chapter 3.5 1.7 cm Absolute accuracy @ 25 °C ±0.5 °C temperature3 0 ... +65 °C ±1.0 °C PSRR (DC) PSRR full VDD range ±0.005 Pa/ mV Long term stability4 APstab 12 months ±1.0 hPa Solder drifts Minimum solder height 50 um -0.5 +2 hPa Start-up time ^startup Time to first communication after both VDD > 1.58V and VDDI0 > 0.65V 2 ms Possible sampling rate fsa triple osrs_t= osrs_p = 1; See chapter 3.8 157 182 tbd5 Hz Standby time accuracy Atstandby ±5 ±25 % 3 Temperature measured by the internal temperature sensor. This temperature value depends on the PC B temperature, sensor element self-heating and ambient temperature and is typically above ambient temperature. 4 Long term stability is specified in the full accuracy operating pressure range 0 ... 65°C 5 Depends on application case, please contact Application Engineer for further questions Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 9 2. Absolute maximum ratings The absolute maximum ratings are provided in Table 3. Parameter Voltage at any supply pin Voltage at any interface pin Storage Temperature Pressure ESD Table 3: Absolute maximum ratings Condition VDD and VDD|0 Pin < 65% rel. H HBM, at any Pin CDM Machine model Unit V V °c hPa kV V V Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 10 3. Functional description The BMP280 consists of a Piezo-resistive pressure sensing element and a mixed-signal ASIC. The ASIC performs A/D conversions and provides the conversion results and sensor specific compensation data through a digital interface. BMP280 provides highest flexibility to the designer and can be adapted to the requirements regarding accuracy, measurement time and power consumption by selecting from a high number of possible combinations of the sensor settings. BMP280 can be operated in three power modes (see chapter 3.6): • sleep mode • normal mode • forced mode In sleep mode, no measurements are performed. Normal mode comprises an automated perpetual cycling between an active measurement period and an inactive standby period. In forced mode, a single measurement is performed. When the measurement is finished, the sensor returns to sleep mode. A set of oversampling settings is available ranging from ultra low power to ultra high resolution setting in order to adapt the sensor to the target application. The settings are predefined combinations of pressure measurement oversampling and temperature measurement oversampling. Pressure and temperature measurement oversampling can be selected independently from 0 to 16 times oversampling (see chapter 3.3.1 and 3.3.2): Temperature measurement Ultra low power Low power Standard resolution High resolution Ultra high resolution BMP280 is equipped with a built-in MR filter in order to minimize short-term disturbances in the output data caused by the slamming of a door or window. The filter coefficient ranges from 0 (off) to 16. In order to simplify the device usage and reduce the high number of possible combinations of power modes, oversampling rates and filter settings, Bosch Sensortec provides a proven set of recommendations for common use-cases in smart-phones, mobile weather stations or flying toys (see chapter 3.4): • Handheld device low-power (e.g. smart phones running Android) • Handheld device dynamic (e.g. smart phones running Android) • Weather monitoring (setting with lowest power consumption) • Elevator / floor change detection • Drop detection • Indoor navigation Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 11 3.1 Block diagram Figure 1 shows a simplified block diagram of the BMP280: Pressure/ temperature sensing element Voltage regulator (analog & digital) Voltage reference Analog front-end ADC Logic OSCPORNVM —qsdi —üsdo —qsck icsb O- gnd Figure 1: Block diagram of BMP280 3.2 Power management The BMP280 has two separate power supply pins • VDd is the main power supply for all internal analog and digital functional blocks • Vddio is a separate power supply pin, used for the supply of the digital interface A power-on reset generator is built in which resets the logic circuitry and the register values after the power-on sequence. There are no limitations on slope and sequence of raising the VDd and VDD|0 levels. After powering up, the sensor settles in sleep mode (see 3.6.1). Warning. Holding any interface pin (SDI, SDO, SCK or CSB) at a logical high level when VDdio is switched off can permanently damage the device due caused by excessive current flow through the ESD protection diodes. If Vddio is supplied, but VDd is not, the interface pins are kept at a high-Z level. The bus can therefore already be used freely before the BMP280 VDd supply is established. 3.3 Measurement flow The BMP280 measurement period consists of a temperature and pressure measurement with selectable oversampling. After the measurement period, the data are passed through an optional MR filter, which removes short-term fluctuations in pressure (e.g. caused by slamming a door). The flow is depicted in the diagram below. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 12 Start \ ^measurement cycled 1 Measure temperature (oversampling set by osrst; skip if osrst = 0) Measure pressure (oversampling set by osrsp; skip if osrs p = 0) Copy ADC values to filter memory (initalises MR filter) Update filter memory using filter memory, ADC value and filter coefficient Copy filter memory to output registers ^ End ^ \measurement cycle/ Figure 2: BMP280 measurement cycle The individual blocks of the diagram above will be detailed in the following subchapters. 3.3.1 Pressure measurement Pressure measurement can be enabled or skipped. Skipping the measurement could be useful if BMP280 is used as temperature sensor. When enabled, several oversampling options exist. Each oversampling step reduces noise and increases the output resolution by one bit, which is stored in the XLSB data register 0xF9. Enabling/disabling the measurement and oversampling settings are selected through the osrs_p[2:0] bits in control register 0xF4. Table 4: osrs_p settings Oversampling setting Pressure oversampling Typical pressure resolution Recommended temperature oversampling Pressure measurement skipped Skipped (output set to 0x80000) As needed Ultra low power xl 16 bit/2.62 Pa xl Low power *2 17 bit/1.31 Pa xl Standard resolution x4 18 bit/0.66 Pa xl High resolution *8 19 bit/0.33 Pa xl Ultra high resolution «16 20 bit/0.16 Pa x2 In order to find a suitable setting for osrs_p, please consult chapter 3.4. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 13 3.3.2 Temperature measurement Temperature measurement can be enabled or skipped. Skipping the measurement could be useful to measure pressure extremely rapidly. When enabled, several oversampling options exist. Each oversampling step reduces noise and increases the output resolution by one bit, which is stored in the XLSB data register OxFC. Enabling/disabling the temperature measurement and oversampling setting are selected through the osrs_t[2:0] bits in control register 0xF4. Table 5: osrs_t settings osrs_t[2:0] Temperature oversampling Typical temperature resolution 000 Skipped (output set to 0x80000) - 001 *1 16 bit/0.0050 °C 010 *2 17 bit/0.0025 °C 011 x4 18 bit/0.0012 °C 100 *8 19 bit/0.0006 °C 101,110, 111 «16 20 bit/0.0003 °C It is recommended to base the value of osrs_t on the selected value of osrs_p as per Table 4. Temperature oversampling above *2 is possible, but will not significantly improve the accuracy of the pressure output any further. The reason for this is that the noise of the compensated pressure value depends more on the raw pressure than on the raw temperature noise. Following the recommended setting will result in an optimal noise-to-power ratio. 3.3.3 MR filter The environmental pressure is subject to many short-term changes, caused e.g. by slamming of a door or window, or wind blowing into the sensor. To suppress these disturbances in the output data without causing additional interface traffic and processor work load, the BMP280 features an internal MR filter. It effectively reduces the bandwidth of the output signals6. The output of a next measurement step is filter using the following formula: data _ filtered data _ filtered _ old ■ (filter _ coefficien t—Y) + data _ ADC filter _coefficien t where data_filtered_old is the data coming from the previous acquisition, and data_ADC is the data coming from the ADC before MR filtering. The MR filter can be configured using the filter[2:0] bits in control register 0xF5 with the following options: 6 Since most pressure sensors do not sample continuously, filtering can suffer from signals with a frequency higher than the sampling rate of the sensor. E.g. environmental fluctuations caused by windows being opened and closed might have a frequency <5 Hz. Consequently, a sampling rate of ODR = 10 Hz is sufficient to obey the Nyquist theorem. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 14 Table 6: filter settings Filter coefficient Samples to reach >75 % of step response Filter off 1 2 2 4 5 11 16 22 In order to find a suitable setting for filter, please consult chapter 3.4. When writing to the register filter, the filter is reset. The next value will pass through the filter and be the initial memory value for the filter. If temperature or pressure measurement is skipped, the corresponding filter memory will be kept unchanged even though the output registers are set to 0x80000. When the previously skipped measurement is re-enabled, the output will be filtered using the filter memory from the last time when the measurement was not skipped. 3.4 Filter selection In order to select optimal settings, the following use cases are suggested: Table 7: Recommended filter settings based on use cases Use case Mode Over-sampling setting osrs_p osrs_t MR filter coeff. (see 3.3.3) Idd DjA] (see 3.7) ODR [Hz] (see 3.8.2) RMS Noise [cm] (see 3.5) handheld device low-power (e.g. Android) Normal Ultra high resolution «16 *2 4 247 10.0 4.0 handheld device dynamic (e.g. Android) Normal Standard resolution x4 *1 16 577 83.3 2.4 Weather monitoring (lowest power) Forced Ultra low power *1 *1 Off 0.14 1/60 26.4 Elevator / floor change detection Normal Standard resolution x4 *1 4 50.9 7.3 6.4 Drop detection Normal Low power *2 *1 Off 509 125 20.8 Indoor navigation Normal Ultra high resolution «16 *2 16 650 26.3 1.6 Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 15 3.5 Noise Noise depends on the oversampling and filter settings selected. The stated values were determined in a controlled pressure environment and are based on the average standard deviation of 32 consecutive measurement points taken at highest sampling speed. This is needed in order to exclude long term drifts from the noise measurement. Table 8: Noise in pressure Typical RMS noise in pressure [Pa] MR filter coefficient Oversampling setting off 2 4 8 16 Ultra low power 3.3 1.9 1.2 0.9 0.4 Low power 2.6 1.5 1.0 0.6 0.4 Standard resolution 2.1 1.2 0.8 0.5 0.3 High resolution 1.6 1.0 0.6 0.4 0.2 Ultra high resolution 1.3 0.8 0.5 0.4 0.2 Table 9: Noise in temperature Typical RMS noise in temperature [°C] Temperature oversampling MR filter off oversampling xl 0.005 oversampling ><2 0.004 oversampling ><4 0.003 oversampling *8 0.003 oversampling ><16 0.002 3.6 Power modes The BMP280 offers three power modes: sleep mode, forced mode and normal mode. These can be selected using the mode[l:0] bits in control register 0xF4. Table 10: mode settings mode[l:0] Mode 00 Sleep mode 01 and 10 Forced mode 11 Normal mode Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 16 3.6.1 Sleep mode Sleep mode is set by default after power on reset. In sleep mode, no measurements are performed and power consumption (IDdsm) is at a minimum. All registers are accessible; Chip-ID and compensation coefficients can be read. 3.6.2 Forced mode In forced mode, a single measurement is performed according to selected measurement and filter options. When the measurement is finished, the sensor returns to sleep mode and the measurement results can be obtained from the data registers. For a next measurement, forced mode needs to be selected again. This is similar to BMP180 operation. Forced mode is recommended for applications which require low sampling rate or host-based synchronization. Iddp Iddt Iddsb Iddsl osrs_t osrs_p P0R s%s ModeM-Ol time Data readout Mode[l:0] = 01 Figure 3: Forced mode timing diagram 3.6.3 Normal mode Normal mode continuosly cycles between an (active) measurement period and an (inactive) standby period, whose time is defined by tstandby The current in the standby period (Iddsb) is slightly higher than in sleep mode. After setting the mode,measurement and filter options, the last measurement results can be obtained from the data registers without the need of further write accesses. Normal mode is recommended when using the MR filter, and useful for applications in which short-term disturbances (e.g. blowing into the sensor) should be filtered. Iddp Iddt Iddsb Iddsl osrs_t osrs_p ^standby 1 ! j 1— 1— J ! Q. ;Q- Q. Q. 1— 1— Q. Q. Q. Q. c c c c c c c c c c CD CD CD CD CD CD CD CD CD CD CD CD E E E E E E E E E E E E CD CD CD 1 CD CD CD CD CD CD CD CD CD asui asui = \ = asui asui >4) - ( ( BMP2 80_S32_t) dig_Tl) ) * ((adc_T»4) - ( (BMP28 0_S32_t) dig_Tl) ) ) » 12) * ((BMP280_S32_t)dig_T3)) >> 14; t_fine - varl + var2; T = (t_fine * 5 + 128) >> 8; return T; ) // Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 integer bits and 8 fractional bits). // Output value of "24674867" represents 24674867/256 = 96386.2 Pa = 963.862 hPa BMP280_U32_t bmp280_compensate_P_int64(BMP280_S32_t adc_P) i BMP280_S64_t varl, var2, p; varl = ((BMP280_S64_t)t_fine) - 128000; var2 = varl * varl * (BMP280_S64_t)dig_P6; var2 = var2 + ((varl*(BMP280_S64_t)dig_P5)<<17); var2 = var2 + ( ( ( BMP2 80_S64_t) dig_P4 ) «35 ) ; varl = ((varl * varl * (BMP280_S64_t)dig_P3)>>8) + ((varl * (BMP280_S64_t)dig_P2)<<12); varl = ( ( ( ( (BMP28 0_S64_t) 1) «47) +varl) ) * ( ( BMP28 0_S64_t) dig_Pl) »33; if (varl == 0) i return 0; // avoid exception caused by division by zero ) p = 1048576-adc_P; p= (((p<<31)-var2)*3125)/varl; varl = ( ( (BMP280_S64_t) dig_P9) * (p»13) * (p»13)) » 25; var2 = (((BMP280_S64_t)dig_P8) * p) >> 19; p = ( (p + varl + var2) » 8) + ( ( (BMP28 0_S64_t) dig_P7 ) «4) ; return (BMP280_U32_t)p; 3.12 Calculating pressure and temperature The following figure shows the detailed algorithm for pressure and temperature measurement. This algorithm is available to customers as reference C source code ("BMP28x_ API") from Bosch Sensortec and via its sales and distribution partners. Please contact your Bosch Sensortec representative for details. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 23 Calculation of pressure and temperature for BMP280 Sample trimming values Register Address (LSB.' MSB: Name Value Type 0x8810x83 d g_T1 27504 unsigned short GxSAJOxOB d g_T2 26435 short OX8C/0X8D d g_T3 -1000 short 0X8E 1 0X8F d g_P1 36477 jr e ::ned short 0X30 1 0X01 d g_P2 -10685 short 0x0210x33 d g_P3 3024 short 0x04/0x05 d g_P4 2855 short 0x3610x37 d g_P5 140 short 0x081 0x00 d g_P6 -7 short 0X3AJ0X3B d g_P7 15500 short Ox9C/0xOD d g_P8 -14600 short 0X3E 1 0X3F dig_P9 6000 short OxAO 1 0xA1 Sample measurement values Register Address (MSB 1LSB/XLSB) Name Value Type 0xF7/0xF8J0xF9[7.4] UT [20 bit] 519888 signed long [*) 0xFA/0xFB/0xFC[7:4] UP [20 bit| 415148 signed long n (*} Value is always positive, even though the compensation functions expect a signed integer as input (*) Value is always positive, even though the compensation functions expect a signed integer as input VaM - 1257:!;.urir1 = ([( Hc_T)r1S384.0 -(( )dig_T1)r102+0)" [[ )dig_T2); Var2 = -370,3917052 var2 = ([[[double]adc_T]ŕ131072.0 - [[double)dig_T1)r8192.0) ■ [[[double)adc_T]r131072.0 - [(double) dig_T1)r3192.0]]" ([doijble)dici_T3]; tfine = 128422 tjine = [BMP280_S32_t)[var1 * ii\2\ t= 25,08 Temperature [CG] t = [vari*var£]f5i20.o: integer result C™): 250Ä Temperature {1/100 "Cj varl = 211,1435029 uar1 = ([double]t_finer2.u) ■ 64000.0; var2 = -9,523652701 var2 = varl- varl- [(double)dig_Pe) ŕ32768.0; var2 = 59110,55716 var2 = var2 * varl" ((double)dig_P5)" 2.0; var2 - 137120057,7 uar2 = (var2í4.u)+[(fdouble)dig_P+)- 65536.0); varl = -4,302618389 varl = ([[double]dig_P3]- varl- varl ŕ524288.0 varl = 36472,21037 varl = [1.0 « vari ŕ32768.rj]-[[ )dig_P1]: P = '333428 p = 104S57S.0-(double)adc_P: P = 100717,3456 p = [p ■ (uar2ŕ4096.0]]- 6250.0ŕ uar1; varl = 23342.24444 varl = ([double]dig_P9]" p" p' 21+7483648 0; var2 = -44875,50492 var2 = p- [[double]dig_P8] ŕ32768.0: P = 100553,27 Pressure [Pa] p = p * [var! + varí * |(double)dig_P7)) ŕ16.0; nt32 result 100653 Pressure {Pa} nt64 result ("): 25767236 Pressure [W256 Pa] (**)The actual result otthe integer calculation -ia.. ce.iete slightl.. fro "i the .allies shown here due to integer calculation rounding errors Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 24 4. Global memory map and register description 4.1 General remarks All communication with the device is performed by reading from and writing to registers. Registers have a width of 8 bits. There are several registers which are reserved; they should not be written to and no specific value is guaranteed when they are read. For details on the interface, consult chapter 5. 4.2 Memory map The memory map is given in Table 18 below. Reserved registers are not shown. Table 18: Memory map Register Name Address bit7 bit6 bit5 bit4 bit3 bit2 bit1 bitO Reset state temp xlsb OxFC temp_xlsb<7:4> 0 0 0 0 0x00 temp Isb OxFB temp_lsb<7:0> 0x00 temp msb Ox FA temp_msb<7:0> 0x80 press xlsb 0xF9 press_xlsb<7:4> | 0 I 0 I 0 I 0 0x00 press Isb 0xF8 press_lsb<7:0> 0x00 press msb 0xF7 press msb<7:0> 0x80 confiq 0xF5 t sb[2:0l filter[2:01 |spi3w en[01 0x00 Ctrl meas 0xF4 osrs_t[2:0l osrs_p[2:01 mode[1:0l 0x00 rwnn status reset uxro OxEO jagg]'iicaaui m iyiwl!sss! |||m u|jucuc|v reset[7:0] uxuu 0x00 Id Ox DO chip_id[7:01 0x58 callb25...callb00 0xA1 ...0x88 calibration data individual Registers: Type: Reserved registers Calibration data Control reaisters Data reaisters Status reaisters Revision Reset do not write read only read / write read only read only read only write only 4.3 Register description 4.3.1 Register OxDO "id" The "id" register contains the chip identification number chip_id[7:0], which is 0x58. This number can be read as soon as the device finished the power-on-reset. 4.3.2 Register OxEO "reset" The "reset" register contains the soft reset word reset[7:0]. If the value 0xB6 is written to the register, the device is reset using the complete power-on-reset procedure. Writing other values than 0xB6 has no effect. The readout value is always 0x00. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 25 4.3.3 Register 0xF3 "status" The "status" register contains two bits which indicate the status of the device. Table 19: Register Ox F3 "status" Register 0xF3 "status" Name Description Bit 3 measuring[0] Automatically set to '1' whenever a conversion is running and back to '0' when the results have been transferred to the data registers. BitO im_update[0] Automatically set to '1' when the NVM data are being copied to image registers and back to '0' when the copying is done. The data are copied at power-on-reset 4.3.4 Register 0xF4 "ctrl_meas" The "ctrl_meas" register sets the data acquisition options of the device. Table 20: Register 0xF4 "ctrl_meas" Register 0xF4 Name Description "ctrl meas" Bit 7, 6, 5 Bit 4, 3, 2 Bit 1, 0 osrs_t[2:0] osrs_p[2:0] mode[l:0] Controls oversampling of temperature data. See chapter 3.3.2 for details. Controls oversampling of pressure data. See chapter 3.3.1 for details. Controls the power mode of the device. See chapter 3.6 for details. Table 21: register settings osrs_p osrs_p[2:0] Pressure oversampling 000 Skipped (output set to 0x80000) 001 oversampling xl 010 oversampling *2 011 oversampling ><4 100 oversampling *8 101, Others oversampling ><16 Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 26 Table 22: register settings osrs_t osrs_t[2:Ö\ Temperature oversampling 000 Skipped (output set to 0x80000) 001 oversampling xl 010 oversampling *2 011 oversampling *4 100 oversampling *8 101,110, 111 oversampling ><16 4.3.5 Register 0xF5 "config" The "config" register sets the rate, filter and interface options of the device. Writes to the "config" register in normal mode may be ignored. In sleep mode writes are not ignored. Table 23: Register 0xF5 "config" Register 0xF5 Name Description ■ "config" Bit 7, 6, 5 t_sb[2:0] Controls inactive duration tstandbv in normal mode. See chapter 3.6.3 for details. Bit 4, 3, 2 filter[2:0] Controls the time constant of the MR filter. See chapter 3.3.3 for details. BitO spi3w_en[0] Enables 3-wire SPI interface when set to'1'. See chapter 5.3 for details. 4.3.6 Register 0xF7...0xF9 "press" (msb, Jsb, _xlsb) The "press" register contains the raw pressure measurement output data up[19:0]. For details on how to read out the pressure and temperature information from the device, please consult chapter3.9. Table 24: Register 0xF7 ... 0xF9 "press" Register 0xF7-0xF9 "press" Name Description 0xF7 press_msb[7:0] Contains the MSB part up[19:12] of the raw pressure measurement output data. 0xF8 press_lsb[7:0] Contains the LSB part up[ll:4] of the raw pressure measurement output data. 0xF9 (bit 7, 6, 5, 4) press_xlsb[3:0] Contains the XLSB part up[3:0] of the raw pressure measurement output data. Contents depend on temperature resolution, see table 5. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 27 4.3.7 Register 0xFA...0xFC "temp" (msb, Isb, _xlsb) The "temp" register contains the raw temperature measurement output data ut[19:0]. For details on how to read out the pressure and temperature information from the device, please consult chapter 3.9. Table 25: Register OxFA ... OxFC "temp" Register 0xF7-0xF9 Name Description "press" OxFA temp_msb[7:0] Contains the MSB part ut[19:12] of the raw temperature measurement output data. temp_lsb[7:0] Contains the LSB part ut[ll:4] of the raw temperature measurement output data. OxFC (bit 7, 6, 5, 4) temp_xlsb[3:0] Contains the XLSB part ut[3:0] of the raw temperature measurement output data. Contents depend on pressure resolution, see Table 4. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 28 5. Digital interfaces The BMP280 supports the l2C and SPI digital interfaces; it acts as a slave for both protocols. The PC interface supports the Standard, Fast and High Speed modes. The SPI interface supports both SPI mode '00' (CPOL = CPHA = '0') and mode '11' (CPOL = CPHA = T) in 4-wire and 3-wire configuration. The following transactions are supported: • Single byte write • multiple byte write (using pairs of register addresses and register data) • single byte read • multiple byte read (using a single register address which is auto-incremented) 5.1 Interface selection Interface selection is done automatically based on CSB (chip select) status. If CSB is connected to Vddio, the PC interface is active. If CSB is pulled down, the SPI interface is activated. After CSB has been pulled down once (regardless of whether any clock cycle occurred), the PC interface is disabled until the next power-on-reset. This is done in order to avoid inadvertently decoding SPI traffic to another slave as PC data. Since power-on-reset is only executed when both VDd and VDdio are established, there is no risk of incorrect protocol detection due to power-up sequence used. However, if PC is to be used and CSB is not directly connected to VDdio but rather through a programmable pin, it must be ensured that this pin already outputs the VDD|0 level during power-on-reset of the device. If this is not the case, the device will be locked in SPI mode and not respond to PC commands. 5.2 PC Interface The PC slave interface is compatible with Philips PC Specification version 2.1. For detailed timings refer to Table 27. All modes (standard, fast, high speed) are supported. SDA and SCL are not pure open-drain. Both pads contain ESD protection diodes to VDDIO and GND. As the devices does not perform clock stretching, the SCL structure is a high-Z input without drain capability. SDI /SCL Vddio o A ■ high-z level shifter output driver (only for SDI) GND GND Figure 6: SDI/SCK ESD drawing The 7-bit device address is lllOllx. The 6 MSB bits are fixed. The last bit is changeable by SDO value and can be changed during operation. Connecting SDO to GND results in slave address 1110110 (0x76); connection it to VDD|0 results in slave address 1110111 (0x77), which Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 29 is the same as BMP180's PC address. The SDO pin cannot be left floating; if left floating, the PC address will be undefined. The PC interface uses the following pins: • SCK: serial clock (SCL) • SDI: data (SDA) • SDO: Slave address LSB (GND = '0', VDD|0 = '1') CSB must be connected to VDD|0 to select PC interface. SDI is bi-directional with open drain to GND: it must be externally connected to VDD|0 via a pull up resistor. Refer to chapter 6 for connection instructions. The following abbreviations will be used in the PC protocol figures: S Start P Stop ACKS Acknowledge by slave ACKM Acknowledge by master NACKM Not acknowledge by master 5.2.1 PC write Writing is done by sending the slave address in write mode (RW = '0'), resulting in slave address 111011X0 ('X' is determined by state of SDO pin. Then the master sends pairs of register addresses and register data. The transaction is ended by a stop condition. This is depicted in Figure 7. Control byte Data byte Start Slave Address RW ACKS Register address (AOh) ACKS Register data - address AOh ACKS S 1 1 1 1 1 1 1 1 1 0 1 1 X ...... 0 1 i i i i i i 1 0 1 0 0 0 0 0 ....... i i i i i i i bit7 bit6 bit5 bit4 bit3 bit2 bid bitO ....... Control byte Data byte Register address (A1h) ACKS Register data - address A1 h ACKS Stop 1 i i i i i i 1 0 1 0 0 0 0 1 ....... i i i i i i i bit7 bit6 bit5 bit4 bit3 bit2 bid bitO ....... P Figure 7: PC multiple byte write (not auto-incremented) 5.2.2 PC read To be able to read registers, first the register address must be sent in write mode (slave address 111011X0). Then either a stop or a repeated start condition must be generated. After this the slave is addressed in read mode (RW = '1') at address 111011X1, after which the slave sends out data from auto-incremented register addresses until a NOACKM and stop condition occurs. This is depicted in Figure 8, where two bytes are read from register 0xF6 and 0xF7. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 30 Control byte Start Slave Address RW ACKS Register address (F6h) ACKS S 1 1 1 1 1 1 1 1 1 0 1 1 X ...... 0 i i i i i i i 11110 110 ....... Data byte Data byte Start Slave Address RW ACKS Register data - address F6h ACKM Register data - address F7h NOACKM Stop S i i i i i i 1 1 1 0 1 1 X ...... 1 i i i i i i i bit7 bit6 bit5 bit4 bit3 bit2 bit1 bitO ....... i i i i i i i bit7 bit6 bit5 bit4 bit3 bit2 bit1 bitO ....... X P Figure 8: PC multiple byte read 5.3 SPI interface The SPI interface is compatible with SPI mode '00' (CPOL = CPHA = '0') and mode '11' (CPOL = CPHA = '1'). The automatic selection between mode '00' and '11' is determined by the value of SCK after the CSB falling edge. The SPI interface has two modes: 4-wire and 3-wire. The protocol is the same for both. The 3-wire mode is selected by setting '1' to the register spi3w_en. The pad SDI is used as a data pad in 3-wire mode. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 31 The SPI interface uses the following pins: • CSB: chip select, active low • SCK: serial clock • SDI: serial data input; data input/output in 3-wire mode • SDO: serial data output; hi-Z in 3-wire mode Refer to chapter 6 for connection instructions. CSB is active low and has an integrated pull-up resistor. Data on SDI is latched by the device at SCK rising edge and SDO is changed at SCK falling edge. Communication starts when CSB goes to low and stops when CSB goes to high; during these transitions on CSB, SCK must be stable. The SPI protocol is shown in Figure 9. For timing details, please review Table 28. csb - ^IAaaaaaaAAaaaaaa/1" sdi sdo moammnacxxxxi RW AD6 AD5 AD4 AD3 AD2 AD1 ADO jDI6 DI5 DI4 DI3 DI2 DM DIO ID07 ID06 D05 D04 D03 D02 D01 DOO tri-state Figure 9: SPI protocol (shown for mode '11' in 4-wire configuration) In SPI mode, only 7 bits of the register addresses are used; the MSB of register address is not used and replaced by a read/write bit (RW = '0' for write and RW = '1' for read). Example: address 0xF7 is accessed by using SPI register address 0x77. For write access, the byte 0x77 is transferred, for read access, the byte 0xF7 is transferred. 5.3.1 SPI write Writing is done by lowering CSB and sending pairs control bytes and register data. The control bytes consist of the SPI register address (= full register address without bit 7) and the write command (bit7 = RW = '0'). Several pairs can be written without raising CSB. The transaction is ended by a raising CSB. The SPI write protocol is depicted in Figure 10. Control byte Data byte Control byte Data byte Start RW Register address (F4h) Data register - address F4h RW Register address (F5h) Data register - adress F5h Stop 0 0 1 1 1 1 1 1 1110 10 0 ...... I I I I I I I bit7 bitG bit5 bit4 bit3 bit2 bit1 bitO ....... 0 I I I I I I 1110 10 1 ...... I I I I I I I bit7 bit6 bit5 bit4 bit3 bit2 bit1 bitO ....... 1 Figure 10: SPI multiple byte write (not auto-incremented) 5.3.2 SPI read Reading is done by lowering CSB and first sending one control byte. The control bytes consist of the SPI register address (= full register address without bit 7) and the read command (bit 7 = RW = '1'). After writing the control byte, data is sent out of the SDO pin (SDI in 3-wire mode); the register address is automatically incremented. The SPI read protocol is shown in Figure 11. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 32 Control byle Data byte Data byte Start RW Register address (F6h) Data register - address F6h Data register - address F7h Stop 0 1 I I I I I I 1110 110 ...... I I I I I I I biti 5 bitH bit13 bit12 bit11 bit10 bit9 bit8 ....... I I I I I I I bit7 bit6 bit5 bit4 bit3 bit2 biti bito ....... 1 Figure 11: SPI multiple byte read 5.4 Interface parameter specification 5.4.1 General interface parameters The general interface parameters are given in Table 26 below. Table 26: interface parameters Parameter Symbol Condition Min Typ Max Units Input - low level Vil_si VDD|0=1.2Vto3.6V 0.2* Vddio V Input - high level Vih_si VDD|0=1.2Vto3.6V 0.8* Vddio V Output - low level for I2C Vol_SDI VDD|0=1.62V, iol=3 mA 0.2* Vddio V Output - low level for I2C Vol_SDI VDDio=1.20V, iol=3 mA 0.23* V _l-2 Vddio Output - low level Vol SD 0 VDD,o=1.62V, iol=l mA 0.2* Vddio V Output - low level Vol SD VDD,o=1.20V, iol=l mA 0.23* V 0_1.2 Vddio Output - high level Voh VDDIO=1.62V, ioh=l mA (SDO, SDI) 0.8* Vddio V Output - high level Voh_1.2 VDD|0=1.2V, ioh=l mA (SDO, SDI) 0.6* Vddio ■ Pull-up resistor Rpull Internal pull-up resistance to VDD|0 70 120 190 kQ I^C bus load capacitor Cb On SDI and SCK 400 PF 5.4.2 l2C timings For PC timings, the following abbreviations are used: • "S&F mode" = standard and fast mode • "HS mode" = high speed mode • Cb = bus capacitance on SDA line All other naming refers to PC specification 2.1 (January 2000). The PC timing diagram is shown in Figure 12. The corresponding values are given in Table 27. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. Figure 12: PC timing diagram Table 27: l2C timings Parameter Symbol Condition Min Typ Max Units SDI setup time tsil;DAT S&F Mode HS mode 160 30 ns ns SDI hold time t|HD;DAT S&F Mode, Cb<100 pF S&F Mode, Cb<400 pF HS mode, Cb<100 pF HS mode, Cb<400 pF 80 90 18 24 115 150 ns ns ns ns SCK low pulse t|_OW HS mode, Cb<100 pF VDDI0 = 1.62 V 160 ns SCK low pulse t|_OW HS mode, Cb<100 pF 210 The above-mentioned I2C specific timings correspond to the following internal added delays: • Input delay between SDI and SCK inputs: SDI is more delayed than SCK by typically 100 ns in Standard and Fast Modes and by typically 20 ns in High Speed Mode. • Output delay from SCK falling edge to SDI output propagation is typically 140 ns in Standard and Fast Modes and typically 70 ns in High Speed Mode. 5.4.3 SPI timings The SPI timing diagram is in Figure 13, while the corresponding values are given in Table 28. All timings apply both to 4- and 3-wire SPI. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 34 Tselupcsb CSB SCK SDI SDO T_se1up_sdi \_/ T highsck Figure 13: SPI timing diagram Table 28: SPI timings Parameter Symbol Condition Min Typ Max Units SPI clock input frequency Fspi 0 10 MHz SCK low pulse T_low_sck 20 SCK high pulse T_high_sck 20 ns SDI setup time T_setup_sdi 20 ns SDI hold time T_hold_sdi 20 ns SDO output delay T_delay_sdo 25pF load, VDD|0=1.6V min 30 ns SDO output delay T_delay_sdo 25pF load, VDD|0=1.2V min 40 ns CSB setup time T_setup_csb 20 ns CSB hold time T_hold_csb 20 ns Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 35 6. Pin-out and connection diagram 6.1 Pin-out 7 GND 6 Vddio Vent hole TOP VIEW (pads not visible) 1 GND 2 CSB 3 SDI 1 GND 2 CSB 3 SDI 4 SCK o Pin 1 marker BOTTOM VIEW (pads visible) 7 GND 6 Vddio 5 SDO Figure 14: Pin-out top and bottom view Table 29: Pin description Pin Name I/O Type Description Connect to SPI4W SPI 3W PC GND Supply Ground GND 2 CSB In Chip select CSB CSB Vddio 3 SDI In/Out Serial data input SDI SDI/SDO SDA 4 SCK In Serial clock input SCK SCK SCL GND for ■ SDO In/Out Serial data output SDO DNC default address 6 Vddio Supply Digital interface supply Vddio GND Supply Ground GND 8 VDD Supply Analog supply Vdd Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 36 6.2 Connection diagram 4-wire SPI SDO- :Ci 'DDIO Vent hole TOP VIEW (pads not visible) ■CSB ■SDI ■SCK Figure 15: 4-wire SPI connection diagram (Pinl marking indicated) Note: the recommended value for Ci, C2 is 100 nF. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 37 6.3 Connection diagram 3-wire SPI Vent hole TOP VIEW (pads not visible) csb sdi/sdo sck Figure 16: 3-wire SPI connection diagram (Pinl marking indicated) Note: the recommended value for Ci, C2 is 100 nF. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 38 6.4 Connection diagram l2C I2C address bit 0 GND:'0';VDDIO:T' Vddio :Ci Vent hole TOP VIEW (pads not visible) ■SDA ■SCL Figure 17: l2C connection diagram (Pinl marking indicated) Notes: The recommended value for Ci, C2 is 100 nF. A direct connection between CSB and VDD|0 is recommended. If CSB is detected as low during startup, the interface will be locked into SPI mode. See chapter 5.1. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 39 7. Package, reel and environment 7.1 Outline dimensions The sensor housing is an 8-pin metal-lid LGA 2.0 * 2.5* 0.95 mm3 package. Its dimensions are depicted in Figure 18. o in m cj p r- o |Q|0.1|C A , ?.?5 2.5O±0.10 O.S25±0.10 A iSOJOiO.10 Q|0.1|C| Ee Li 2 1 Figure 18: Package outline dimensions for top, bottom and side view Note: General tolerances are ±50 urn (linear) and ±1° urn (angular) Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 40 7.2 Landing pattern recommendation For the design of the landing pattern, the following dimensioning is recommended: 0.5 o LO c\i LO CD 0.55 2.0 Figure 19: Recommended landing pattern (top view); dimensions are in mm Note: red areas demark exposed PCB metal pads. In case of a solder mask defined (SMD) PCB process, the land dimensions should be defined by solder mask openings. The underlying metal pads are larger than these openings. In case of a non solder mask defined (NSMD) PCB process, the land dimensions should be defined in the metal layer. The mask openings are larger than the these metal pads. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 41 7.3 Marking 7.3.1 Mass production devices Table 30: Marking of mass production samples Labeling Name Symbol Remark Lot counter CCC 3 alphanumeric digits, variable to generate mass production trace-code CCC TL • Product number T 1 alphanumeric digit, fixed to identify product type, T = "K" "K" is associated with the product BMP280 (part number 0 273 300 354) Sub-con ID L 1 alphanumeric digit, variable to -ntify sub-con (L = "P", L = "U", L = "N"or L = "W") Orientation Vent hole marker w 7.3.2 Engineering samples Table 31: Marking of engineering samples Labeling ■1 Name Symbol Remark Eng. Sample ID N 1 alphanumeric digit, fixed to identify engineering sample, N = " * " or "e" or "E" XXN CC • Sample ID XX 2 alphanumeric digits, variable to generate trace-code Counter ID CC 2 alphanumeric digits, variable to generate trace-code Orientation Vent hole marker w Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 42 7.4 Soldering guidelines The moisture sensitivity level of the BMP280 sensors corresponds to JEDEC Level 1, see also: • IPC/JEDEC J-STD-020C "Joint Industry Standard: Moisture/Reflow Sensitivity Classification for non-hermetic Solid State Surface Mount Devices" • IPC/JEDEC J-STD-033A "Joint Industry Standard: Handling, Packing, Shipping and Use of Moisture/Reflow Sensitive Surface Mount Devices". The sensor fulfils the lead-free soldering requirements of the above-mentioned IPC/JEDEC standard, i.e. reflow soldering with a peak temperature up to 260°C. The minimum height of the solder after reflow shall be at least 50um. This is required for good mechanical decoupling between the sensor device and the printed circuit board (PCB). Profile Feature Pb-Free Assembly Average Ramp-Up Rate (Tsmax to Tp) 3" C/second max. Preheat - Temperature Min (Tsmin) - Temperature Max (Tsmax) - Time (tsmin to tsmax) 150 °C 200 °C 60-180 seconds Time maintained above: - Temperature (TL) - Time (tj 217 °C 60-150 seconds Peak/Classification Temperature (Tp) 260 °C Time within 5 °C of actual Peak Temperature (tp) 20-40 seconds Ramp-Down Rate 6 °C/second max. Time 25 °C to Peak Temperature 8 minutes max. Note 1: All temperatures refer to topside of the package, measured on the package body surface. <-1 25°C to Peak-H Time n=> ipc-020c-5-1 Figure 20: Soldering profile Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 43 7.5 Tape and reel specification 7.5.1 Dimensions 0.30 LQ5- R 0.20 MAX. 2.00 +.05 SEE NOTE 2 4,OD SEE NOTE I 0 1,5 +D.1/-0.0 0 1,50 HIN I fi 12,0 +0.3/-D, 1,75 ±,10 __t 1 J O TYP 2,80 2,30 1,20 Figure 21: Tape and Reel dimensions 5,50 ±,05 SEE HÜTE 2 Quantity per reel: 10 kpcs. 7.5.2 Orientation within the reel mm 8 7 6 5 reel direction Figure 22: Orientation within tape Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 44 7.6 Mounting and assembly recommendations In addition to "Handling, soldering & mounting instructions BMP280", the following recommendations should be taken into consideration when mounting a pressure sensor on a printed-circuit board (PCB): • The clearance above the metal lid shall be 0.1mm at minimum. • For the device housing appropriate venting needs to be provided in case the ambient pressure shall be measured. • Liquids shall not come into direct contact with the device. • During operation the sensor chip is sensitive to light, which can influence the accuracy of the measurement (photo-current of silicon). The position of the vent hole minimizes the light exposure of the sensor chip. Nevertheless, BST recommends to avoid the exposure of BMP280 to strong light sources. • Soldering may not be done using vapor phase processes since the sensor might be damaged. 7.7 Environmental safety 7.7.1 RoHS The BMP280 sensor meets the requirements of the EC restriction of hazardous substances (RoHS) directive, see also: Directive 2011/65/EU of the European Parliament and of the Council of 8 June 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment. 7.7.2 Halogen content The BMP280 is halogen-free. For more details on the analysis results please contact your Bosch Sensortec representative. 7.7.3 Internal package structure Within the scope of Bosch Sensortec's ambition to improve its products and secure the mass product supply, Bosch Sensortec qualifies additional sources (e.g. 2nd source) for the LGA package of the BMP280. While Bosch Sensortec took care that all of the technical packages parameters are described above are 100% identical for all sources, there can be differences in the chemical content and the internal structural between the different package sources. However, as secured by the extensive product qualification process of Bosch Sensortec, this has no impact to the usage or to the quality of the BMP280 product. 8. Appendix 1: Computation formulae for 32 bit systems 8.1 Compensation formula in floating point Please note that it is strongly advised to use the API available from Bosch Sensortec to perform readout and compensation. If this is not wanted, the code below can be applied at the user's risk. Both pressure and temperature values are expected to be received in 20 bit format, positive, stored in a 32 bit signed integer. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 45 The variable t_fine (signed 32 bit) carries a fine resolution temperature value over to the pressure compensation formula and could be implemented as a global variable. The data type "BMP280_S32_t" should define a 32 bit signed integer variable type and could usually be defined as "long signed inf. The revision of the code is rev.1.1. // Returns temperature in DegC, double precision. Output value of "51.23" equals 51.23 DegC. // t_fine carries fine temperature as global value BMP28 0_S32_t t_fine; double bmp280_compensate_T_double(BMP280_S32_t adc_T) i double varl, var2, T; varl = (((double)adc_T)/16384.0 - ((double)dig_Tl)/1024.0) * ((double)dig_T2); var2 = ((((double)adc_T)/131072.0 - ((double)dig_Tl)/8192.0) * (((double)adc_T)/131072.0 - ((double) dig_Tl)/8192.0)) * ((double)dig_T3); t_fine = (BMP280_S32_t)(varl + var2); T = (varl + var2) / 5120.0; return T; ) // Returns pressure in Pa as double. Output value of "96386.2" equals 96386.2 Pa - 963.862 hPa double bmp280_compensate_P_double(BMP280_S32_t adc_P) i double varl, var2, p; varl = ((double)t_fine/2.0) - 64000.0; var2 = varl * varl * ((double)dig_P6) / 32768.0; var2 = var2 + varl * ((double)dig_P5) * 2.0; var2 = (var2/4.0)+(((double)dig_P4) * 65536.0); varl = (((double)dig_P3) * varl * varl / 524288.0 + ((double)dig_P2) * varl) / 524288.0; varl = (1.0 + varl / 32768.0)*((double)dig_Pl); if (varl == 0.0) i return 0; // avoid exception caused by division by zero ) p = 1048576.0 - (double)adc_P; p = (p - (var2 / 4096.0)) * 6250.0 / varl; varl = ((double)dig_P9) * p * p / 2147 48 3648.0; var2 = p * ((double)dig_P8) / 32768.0; p = p + (varl + var2 + ((double)dig_P7)) / 16.0; return p; ) 8.2 Compensation formula in 32 bit fixed point Please note that it is strongly advised to use the API available from Bosch Sensortec to perform readout and compensation. If this is not wanted, the code below can be applied at the user's risk. Both pressure and temperature values are expected to be received in 20 bit format, positive, stored in a 32 bit signed integer. The variable t_fine (signed 32 bit) carries a fine resolution temperature value over to the pressure compensation formula and could be implemented as a global variable. The data type "BMP280_S32_t" should define a 32 bit signed integer variable type and can usually be defined as "long signed inf. The data type "BMP280_U32_f should define a 32 bit unsigned integer variable type and can usually be defined as "long unsigned inf. Compensating the pressure value with 32 bit integer has an accuracy of typically 1 Pa (1-sigma). At very high filter levels this adds a noticeable amount of noise to the output values and reduces their resolution. // Returns temperature in DegC, resolution is 0.01 DegC. Output value of "5123" equals 51.23 DegC. // t_fine carries fine temperature as global value BMP28 0_S32_t t_fine; BMP280_S32_t bmp280_compensate_T_int32(BMP280_S32_t adc_T) { BMP280_S32_t varl, var2, T; Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. fi BOSCH Datasheet BMP280 Digital Pressure Sensor Page 46 Varl = ( ( ( (adc_T»3) - ( (BMP280_S32_t) dig_Tl«l) ) ) * ( (BMP2 80_S32_t) dlg_T2) ) » 11; var2 = ( ( ( ( (adc_T>>4) - ( ( BMP2 80_S32_t) dlg_Tl) ) * ((adc_T»4) - ( (BMP28 0_S32_t) dlg_Tl) ) ) » 12) * ((BMP280_S32_t)dlg_T3)) >> 14; t_fine - Varl + var2; T = (t_flne * 5 + 128) >> 8; return T; // Returns pressure in Pa as unsigned 32 bit integer. Output value of "96386" equals 96386 Pa - 963.86 hPa BMP280_U32_t bmp280_compensate_P_int32(BMP280_S32_t adc_P) i BMP280_S32_t varl, var2; BMP280_U32_t p; varl = (((BMP280_S32_t)t_fine)>>1) - (BMP280_S32_t)64000; var2 = (((varl>>2) * (varl>>2)) >> 11 ) * ((BMP280_S32_t)dig_P6); var2 = var2 + ((varl*((BMP280_S32_t)dig_P5))<<1); var2 = (var2>>2)+(((BMP280_S32_t)dig_P4)<<16); varl = ( ( (dig_P3 * (((varl>>2) * (varl»2)) » 13 ) ) >> 3) + ( ( ( (BMP280_S32_t) dig_P2) * varl) >>1) ) »18; varl =( ( ( (327 68+varl) ) * ( ( BMP2 80_S32_t) dig_Pl) ) »15) ; if (varl == 0) i return 0; // avoid exception caused by division by zero ) p = ( ( (BMP280_U32_t) ( ( ( BMP2 80_S32_t) 104 8576 ) -adc_P) - (var2»12) ) ) *3125; if (p < 0x80000000) i p = (p « 1) / ((BMP280_U32_t)varl); p = (p / (BMP280_U32_t)varl) * 2; ) varl = ( ( (BMP280_S32_t) dig_P9) * ( ( BMP2 80_S32_t) ( ( (p>>3) * (p»3) ) »13 ) ) ) »12 ; var2 = ( ( (BMP280_S32_t) (p»2) ) * ( ( BMP2 80_S32_t) dig_P8 ) ) »13 ; p = (BMP280_U32_t)((BMP280_S32_t)p + ((varl + var2 + dig_P7) >> 4)); return p; else Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 47 9. Legal disclaimer 9.1 Engineering samples Engineering Samples are marked with an asterisk (*) or (e) or (E). Samples may vary from the valid technical specifications of the product series contained in this data sheet. They are therefore not intended or fit for resale to third parties or for use in end products. Their sole purpose is internal client testing. The testing of an engineering sample may in no way replace the testing of a product series. Bosch Sensortec assumes no liability for the use of engineering samples. The Purchaser shall indemnify Bosch Sensortec from all claims arising from the use of engineering samples. 9.2 Product use Bosch Sensortec products are developed for the consumer goods industry. They are not designed or approved for use in military applications, life-support appliances, safety-critical automotive applications and devices or systems where malfunctions of these products can reasonably be expected to result in personal injury. They may only be used within the parameters of this product data sheet. The resale and/or use of products are at the Purchaser's own risk and the Purchaser's own responsibility. The Purchaser shall indemnify Bosch Sensortec from all third party claims arising from any product use not covered by the parameters of this product data sheet or not approved by Bosch Sensortec and reimburse Bosch Sensortec for all costs in connection with such claims. The Purchaser accepts the responsibility to monitor the market for the purchased products, particularly with regard to product safety, and inform Bosch Sensortec without delay of any security relevant incidents. 9.3 Application examples and hints With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, Bosch Sensortec hereby disclaims any and all warranties and liabilities of any kind, including without limitation warranties of noninfringement of intellectual property rights or copyrights of any third party. The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. They are provided for illustrative purposes only and no evaluation regarding infringement of intellectual property rights or copyrights or regarding functionality, performance or error has been made. Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 I May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 48 10. Document history and modification Rev. No Chapter Description of modification/changes Date 0.1 Document creation 2012-08-06 1.0 9.2 Change of product use 2013-11-26 Table 2 Update of min/max data (only for restricted version) Added comment on the sampling rate 1.1 1, 3.3.1 Changed value for resolution, values for osrs_p settings changed 2014-02-10 5.2 Changed sentence and added drawing 2014-02-18 3.7 Added max values for current consumption 2014-05-08 1.11 4.5.3 Modified write in normal mode 2014-06-25 5.2 Modified SDI/SCK ESD drawing 1.12 1 Changed min/max values for standby current, only valid for 25 °C 2014-07-12 Table 1 Pressure resolution 0.16Pa 2014-07-12 1.13 Page 2 New technical reference codes added 2014-11-12 7.3 New details about laser marking added 1.14 Table 6 Changed contents of table 2015-05-04 Page 1 Removed TRC 0 273 300 354 & 0273 300 391 Page 44 Updated RoHS directive to 2011/65/EU effective 8 June 2011 2015-05-07 Bosch Sensortec GmbH Gerhard- Kindler-Strasse 8 72770 Reutlingen/ Germany contact® bosch-sensortec.com www.bosch-sensortec.com Modifications reserved | Printed in Germany Specifications subject to change without notice Document number: BST-BMP280-DS001-11 Revision_1.14_052015 Bosch Sensortec BST-BMP280-DS001-11 | Revision 1.14 | May 2015 © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication. BOSCH Datasheet BMP280 Digital Pressure Sensor Page 49 BST-BMP280-DS001-11 | Revision 1.14 I May 2015 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even 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 symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice. Not intended for publication.