Data sheet
BMP280
Digital Pressure Sensor
Bosch Sensortec
BMP280: Data sheet
Document revision
1.15
Document release date
October 15 , 2015
Document number
BST-BMP280-DS001-12
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.
th
Datasheet
BMP280 Digital Pressure Sensor
Page 2
BMP280
DIGITAL PRESSURE SENSOR
Key parameters
Pressure range
300 … 1100 hPa
(equiv. to +9000…-500 m above/below sea level)
Package
8-pin LGA metal-lid
Footprint : 2.0 × 2.5 mm², height: 0.95 mm
Relative accuracy
(950 … 1050hPa @25°C)
±0.12 hPa, equiv. to ±1 m
Absolute accuracy
(950 ...1050 hPa, 0 ...+40 °C)
typ. ±1 hPa
Temperature coefficient offset 1.5 Pa/K, equiv. to 12.6 cm/K
(25 ... 40°C @900hPa)
Digital interfaces
I²C (up to 3.4 MHz)
SPI (3 and 4 wire, up to 10 MHz)
Current consumption
2.7µA @ 1 Hz sampling rate
Temperature range
-40 … +85 °C
RoHS compliant, halogen-free
MSL 1
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
Vertical velocity indication (e.g. rise/sink speed)
Target devices
Handsets such as mobile phones, tablet PCs, GPS devices
Navigation systems
Home weather stations
Flying toys
Watches
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
Bosch Sensortec
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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.
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 µA @1Hz 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 indoor navigation, fitness 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 × 3.8 mm
2.0 × 2.5 mm
Minimum VDD
1.80 V
1.71 V
Minimum VDDIO
1.62 V
1.20 V
Current consumption @3 Pa RMS noise
12 µA
2.7 µA
RMS Noise
3 Pa
1.3 Pa
Pressure resolution
1 Pa
0.16 Pa
Temperature resolution
0.1°C
0.01°C
Interfaces
I²C
I²C & 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
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
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 IIR 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 0XD0 “ID” .................................................................................................................... 24
4.3.2 REGISTER 0XE0 “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” (_MSB, _LSB, _XLSB) .................................................................. 26
4.3.7 REGISTER 0XFA…0XFC “TEMP” (_MSB, _LSB, _XLSB)................................................................... 27
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
Datasheet
BMP280 Digital Pressure Sensor
Page 5
5. DIGITAL INTERFACES ............................................................................................................ 28
5.1 INTERFACE SELECTION ...................................................................................................... 28
5.2 I²C INTERFACE.................................................................................................................. 28
5.2.1 I²C WRITE .................................................................................................................................... 29
5.2.2 I²C READ ..................................................................................................................................... 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 I²C 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 I2C ................................................................................................ 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-DS001-12 | Revision 1.15 | October 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.
Datasheet
BMP280 Digital Pressure Sensor
Page 6
9.2 PRODUCT USE .................................................................................................................. 47
9.3 APPLICATION EXAMPLES AND HINTS ................................................................................... 47
10. DOCUMENT HISTORY AND MODIFICATION ..................................................................... 48
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
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 ±3 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
2
Condition
Min
Typ
Max
Units
operational
-40
25
+85
full accuracy
0
+65
1100
hPa
Operating temperature
range
TA
Operating pressure
range
P
full accuracy
300
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
2.8
4.2
µA
720
1120
µA
Supply current
IDD,LP
1 Hz forced mode,
pressure and
temperature, lowest
power
Peak current
Ipeak
during pressure
measurement
Current at temperature
measurement
IDDT
Sleep current
1
Symbol
1
325
°C
µA
IDDSL
25 °C
0.1
0.3
µA
Standby current
(inactive period of
2
normal mode)
IDDSB
25 °C
0.2
0.5
µA
Relative accuracy
pressure
VDD = 3.3V
700 … 900hPa
25 . . . 40 °C
±0.12
hPa
Arel
±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.
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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© 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.
Datasheet
BMP280 Digital Pressure Sensor
Offset temperature
coefficient
TCO
Resolution of
output data in ultra high
resolution mode
PSRR (DC)
P
full
300 . . . 1100 hPa
0 . . . 65 °C
±1.0
hPa
P
Pressure
0.0016
hPa
T
Temperature
0.01
°C
Vp,full
Full bandwidth, ultra
high resolution
See chapter 3.5
1.3
Pa
11
cm
Lowest bandwidth,
ultra high resolution
See chapter 3.5
0.2
Pa
Vp,filtered
1.7
cm
@ 25 °C
±0.5
°C
0 . . . +65 °C
±1.0
°C
A
R
R
T
A
Pstab
12 months
Minimum solder
height 50 µm
Start-up time
tstartup
Time to first
communication after
both VDD > 1.58V and
VDDIO > 0.65V
Possible sampling rate
fsample
osrs_t = osrs_p = 1;
See chapter 3.8
Standby time accuracy
tstandby
Solder drifts
cm/K
hPa
full VDD range
4
12.6
±1.7
PSRR
Long term stability
Pa/K
300 . . . 1100 hPa
-20 . . . 0 °C
A
Noise in pressure
Absolute accuracy
3
temperature
±1.5
ext
P
Absolute accuracy
pressure
900hPa
25 . . . 40 °C
Page 8
±0.005
±1.0
-0.5
157
Pa/
mV
hPa
+2
hPa
2
ms
182
tbd
5
Hz
±5
±25
%
3
Temperature measured by the internal temperature sensor. This temperature value depends on the PCB 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
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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© 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.
Datasheet
BMP280 Digital Pressure Sensor
Page 9
2. Absolute maximum ratings
The absolute maximum ratings are provided in Table 3.
Table 3: Absolute maximum ratings
Parameter
Condition
Min
Max
Unit
Voltage at any supply pin
VDD and VDDIO Pin
-0.3
4.25
V
Voltage at any interface pin
Storage Temperature
Pressure
≤ 65% rel. H.
-0.3
-45
0
ESD
HBM, at any Pin
CDM
Machine model
VDDIO + 0.3
+85
20 000
±2
±500
±200
V
°C
hPa
kV
V
V
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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© 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.
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 IIR 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
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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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.
Datasheet
BMP280 Digital Pressure Sensor
Page 11
3.1 Block diagram
Figure 1 shows a simplified block diagram of the BMP280:
VDD
Voltage
regulator
(analog &
digital)
Pressure/
temperature
sensing
element
Analog
front-end
VDDIO
Voltage
reference
ADC
Logic
OSC POR NVM
I
n
t
e
r
f
a
c
e
SDI
SDO
SCK
CSB
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 VDDIO 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 IIR filter, which removes short-term fluctuations in pressure (e.g. caused by slamming a
door). The flow is depicted in the diagram below.
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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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.
Datasheet
BMP280 Digital Pressure Sensor
Page 12
Start
measurement cycle
Measure temperature
(oversampling set by osrs_t;
skip if osrs_t = 0)
IIR filter enabled?
No
Yes
Measure pressure
(oversampling set by osrs_p;
skip if osrs_p = 0)
IIR filter initialised?
Copy ADC values
to filter memory
(initalises IIR filter)
No
Yes
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
×1
16 bit / 2.62 Pa
×1
Low power
×2
17 bit / 1.31 Pa
×1
Standard resolution
×4
18 bit / 0.66 Pa
×1
High resolution
×8
19 bit / 0.33 Pa
×1
Ultra high resolution
×16
20 bit / 0.16 Pa
×2
In order to find a suitable setting for osrs_p, please consult chapter 3.4.
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
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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.
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 0xFC. 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
×4
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 IIR 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 IIR 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 1) 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 IIR filtering.
The IIR 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
>3) – ((BMP280_S32_t)dig_T1 11;
var2 = (((((adc_T>>4) – ((BMP280_S32_t)dig_T1)) * ((adc_T>>4) – ((BMP280_S32_t)dig_T1))) >> 12) *
((BMP280_S32_t)dig_T3)) >> 14;
t_fine = var1 + 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)
{
BMP280_S64_t var1, var2, p;
var1 = ((BMP280_S64_t)t_fine) – 128000;
var2 = var1 * var1 * (BMP280_S64_t)dig_P6;
var2 = var2 + ((var1*(BMP280_S64_t)dig_P5) 25;
var2 = (((BMP280_S64_t)dig_P8) * p) >> 19;
p = ((p + var1 + var2) >> 8) + (((BMP280_S64_t)dig_P7)3) – ((BMP280_S32_t)dig_T1 11;
var2 = (((((adc_T>>4) – ((BMP280_S32_t)dig_T1)) * ((adc_T>>4) – ((BMP280_S32_t)dig_T1))) >> 12) *
((BMP280_S32_t)dig_T3)) >> 14;
t_fine = var1 + var2;
T = (t_fine * 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)
{
BMP280_S32_t var1, var2;
BMP280_U32_t p;
var1 = (((BMP280_S32_t)t_fine)>>1) – (BMP280_S32_t)64000;
var2 = (((var1>>2) * (var1>>2)) >> 11 ) * ((BMP280_S32_t)dig_P6);
var2 = var2 + ((var1*((BMP280_S32_t)dig_P5))2)+(((BMP280_S32_t)dig_P4)2) * (var1>>2)) >> 13 )) >> 3) + ((((BMP280_S32_t)dig_P2) * var1)>>1))>>18;
var1 =((((32768+var1))*((BMP280_S32_t)dig_P1))>>15);
if (var1 == 0)
{
return 0; // avoid exception caused by division by zero
}
p = (((BMP280_U32_t)(((BMP280_S32_t)1048576)-adc_P)-(var2>>12)))*3125;
if (p < 0x80000000)
{
p = (p >3) * (p>>3))>>13)))>>12;
var2 = (((BMP280_S32_t)(p>>2)) * ((BMP280_S32_t)dig_P8))>>13;
p = (BMP280_U32_t)((BMP280_S32_t)p + ((var1 + var2 + dig_P7) >> 4));
return p;
}
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
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.
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
Datasheet
BMP280 Digital Pressure Sensor
Page 48
10. Document history and modification
Rev. No
0.1
Chapter
Description of modification/changes
Document creation
9.2
Change of product use
1.0
Date
2012-08-06
Update of min/max data (only for restricted version) 2013-11-26
Table 2
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
4.5.3
Modified write in normal mode
1.11
2014-06-25
5.2
Modified SDI/SCK ESD drawing
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
Page 2
New technical reference codes added
7.3
New details about laser marking added
Table 6
Changed contents of table
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
Page 2, 3
Modified target devices, applications
2015-10-15
1.12
1.13
2014-11-12
2015-05-04
1.14
1.15
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-DS001-12
Revision_1.15_052015
BST-BMP280-DS001-12 | Revision 1.15 | October 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.
Datasheet
BMP280 Digital Pressure Sensor
BST-BMP280-DS001-12 | Revision 1.15 | October 2015
Page 49
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.
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