BMP280Digital barometric pressure sensor

Measure air pressure. Compensate it with temperature.

Manufacturer-referenced

Bosch Sensortec · BMP280

LGA-8BST-BMP280-DS001-26 · October 2021

BMP280 is a miniature digital sensor that measures barometric pressure and temperature. Its sensing elements and mixed-signal electronics share an eight-contact metal-lid LGA package. I²C and SPI provide the interface to a microcontroller; the IC itself has no display or regulator. The BMP280 has no humidity channel; a similar-looking BME280 is a different device. Raw conversion data must be compensated with calibration coefficients read from that individual sensor. Temperature compensation is performed first because the pressure calculation depends on its intermediate result. The example uses both supplies at 3.3 V, two local bypass capacitors and an I²C address of 0x76. Pin numbering runs clockwise in the top view, so pad 1 is at the upper right. The illustrated 25°C and 1000 hPa readings explain units; they are not measurements from a connected sensor.

Real View

BMP280 metal-lid LGA sensor with a vent and eight underside contacts.

Pinout

BMP280LGA-8Top view · clockwise numbering

PCB Footprint

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3D View

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8Physical pins BMP280LGA-8 Manufacturer-referencedBosch Sensortec

Pin diagram

Select a pin to explore its connection

Package map

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BMP280LGA-8Top view · clockwise numbering

Click a lead or use the arrow keys. Top view · clockwise numbering

PIN 1 · Ground

GND

Ground

Function

First ground pad.

How to connect

Join common ground; connect pad 7 too.

Key specifications

Factory calibration belongs to each individual sensor. Read its coefficients, acquire a complete result and apply the manufacturer compensation in the correct order.

Pressure range300–1100 hPa

Main supply1.71–3.6 V

Interface choicesI²C / SPI 3- or 4-wire SPI

Operating temperature−40–85 °C

Operating profile

Supply, signals and operating conditions

BMP280 operating profile
Parameter	Value	Conditions / notes
Bare sensor	LGA-8	2 × 2.5 × .95 mm
I²C address	0x76 / 0x77	Selected by SDO
Typical 1 Hz current	2.7 µA	Pressure and temperature

Package details

BMP280 · LGA-8

Selected package

Selected BMP280 physical package
Property	Details
Manufacturer	Bosch Sensortec
Part number	BMP280
Package	LGA-8
Connections	8 pins
Mounting	SMD
Lead pitch	0.65 mm
Package code	Metal-lid LGA
Thermal reference	Keep the vent open and isolate from board heat

Supply and environment

Recommended operating conditions

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
VDD main supply	1.71–3.6 V	3.3 V in the example
VDDIO supply	1.2–3.6 V	Sets the digital logic domain
Operating temperature	−40 to +85°C	Accuracy conditions are narrower
Pressure range	300–1100 hPa	Absolute pressure
Humidity channel	Not present	Use BME280 if humidity is required
Startup before communication	2 ms	Also wait until status.im_update clears
Sleep current	0.1 µA typical	Sensor sleep; excludes external pull-ups and controller

Do not connect 5 V logic or pull-ups to the bare sensor.

Measurement performance

Typical or stated accuracy conditions

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
Pressure absolute accuracy	±1 hPa typical	950–1050 hPa, 0–40°C
Relative pressure accuracy	±0.12 hPa	700–900 hPa; 25°C
Temperature accuracy	±0.5°C at 25°C	Internal die temperature; board heating affects ambient estimates
Pressure resolution	0.16 Pa	Output resolution is not accuracy
Typical pressure noise	1.3 Pa RMS	Highest resolution, full bandwidth
Filtered pressure noise	0.2 Pa RMS typical	Highest oversampling and lowest bandwidth
Typical current at 1 Hz	2.7 µA	Pressure and temperature

Resolution, noise, accuracy and conversion speed describe different limitations.

Digital interfaces

I²C and SPI configuration

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
I²C chip selection	CSB2 tied to VDDIO	Required from power-on reset
I²C data / clock	SDI3 = SDA; SCK4 = SCL	Pull both bus lines to VDDIO
SDO5 low / high	0x76 / 0x77	Seven-bit addresses; do not float
I²C maximum clock	3.4 MHz	Use the required high-speed protocol; example is 100 kHz
SPI maximum clock	10 MHz	Observe setup, hold and output delay conditions
4-wire SPI	CSB, SCK, SDI, SDO	Separate input and output data
3-wire SPI	CSB, SCK and shared SDI	Set spi3w_en; SDO is unused

A module may contain its own pull-ups or regulator. Inspect its schematic separately.

Registers and calibration

Read whole measurement groups coherently

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
0xD0 chip ID	0x58	Distinguishes the selected part
0xE0 reset	Write 0xB6	Wait for startup / coefficient copy
0xF3 status	Bit 3 measuring; bit 0 im_update	Do not read an old result as a just-triggered conversion
0xF4 ctrl_meas	Temperature / pressure oversampling and mode	Example 0x25 = ×1 / ×1 / forced
0xF5 config	Standby time, IIR and 3-wire selection	Configure in sleep; example filter off
0xF7–0xFC	20-bit pressure + 20-bit temperature	MSB, LSB and upper nibble of XLSB
Calibration	Temperature / pressure from 0x88 onward	Use each chip’s stored coefficients

Preserve signed coefficient types and packed fields; raw ADC data is not already °C, Pa or % RH.

Acquisition modes and timing

Noise, response and current trade-offs

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
Sleep	No measurements	Registers remain accessible
Forced	One measurement, then sleep	Host triggers the next result
Normal	Repeated measurement and standby	Choose standby for the required update rate
Oversampling	Skipped or ×1 / ×2 / ×4 / ×8 / ×16	Each enabled channel configured separately
IIR	Off / 2 / 4 / 8 / 16	Pressure and temperature; not humidity
Example conversion maximum	6.425 ms	×1 temperature and pressure; manufacturer timing formula
Fresh result check	Wait for the conversion to finish	Allow the full bounded duration or observe the busy-to-idle transition

Firmware must allow startup and bus time as well as the acquisition itself.

3.3 V I²C measurement

A bare-sensor connection

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
VDD8 and VDDIO6	3.3 V	Separate 100 nF capacitors to common ground
GND1 and GND7	Common ground	Connect both pads
CSB2	3.3 V	Select I²C from startup
SDO5	GND	Address 0x76
SDA3 and SCL4	3.3 V controller	4.7 kΩ example pull-ups; verify bus rise time
Firmware order	Reset / wait / coefficients / configuration / convert / read	Temperature compensation before dependent channels
Display examples	25.0°C · 1000.0 hPa	Illustrative engineering-unit values, not live readings

The display belongs to the host system, not the sensor package.

Package and assembly

Clockwise top-view numbering

Manufacturer specifications 7 parameters

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Parameter	Value	Conditions / notes
Package body	2 × 2.5 × 0.95 mm	Eight-contact metal-lid LGA
Pad pitch	0.65 mm	Four contacts on each of two opposite sides
Top-view order	Right: 1,2,3,4 · left: 8,7,6,5	Top to bottom; bottom view is mirrored
Vent opening	Keep clear	Avoid coating, adhesive or contamination in the port
Thermal placement	Away from hot ICs and airflow artifacts	Temperature senses package conditions
PCB lands	Authored 0.50 × 0.35 mm; 1.50 mm row centers	Starting pattern checked against the package outline
Humidity handling	No humidity sensing element	Review the complete manufacturer assembly instructions

The bare IC and a breakout module have different size, pinout and supporting circuitry.

Connections by function

Select a pin for its function, connection guidance and electrical notes.

Ground2 pins

Mode and address2 pins

Serial interface2 pins

Supply2 pins

BMP280 working principle: illustrated functional stages, basic circuit and connections — Select the diagram to read it at full resolution.

How it works

3 stages · Explore one step at a time

Step 1 / 3

Power and identify

Supply both domains, wait for startup and NVM copying, then confirm chip ID 0x58 at register 0xD0.

Step 2 / 3

Configure and acquire

write ctrl_meas 0xF4 = 0x25 for ×1 temperature, ×1 pressure and forced mode. Wait for this conversion to complete.

Step 3 / 3

Compensate and display

Burst-read six bytes from 0xF7. Decode raw fields, use this sensor’s calibration and convert pressure from Pa to hPa by dividing by 100.

BMP280 physical LGA top view with CSB high, SDO low, two bypass capacitors and I2C pull-ups to 3.3 V. — Matching named nodes are connected; displayed values are illustrative.

Connect it, step by step

Follow the component values and pin connections

Supply

Bypass VDD and VDDIO independently.

Address

Tie CSB high and SDO low for I²C address 0x76.

Acquire

Read calibrated engineering units through the host firmware.

BMP280 cutaway with sensing elements, ADC, calibration NVM and serial registers. — Original functional architecture; compensation is performed by host software.

Explore the circuit

Select a stage to see its role and connections

Sense

A piezoresistive MEMS element responds to absolute pressure.

Convert

Oversampling and filtering control noise and response.

Compensate

The host combines raw results with individual calibration coefficients.

Selected packageLGA-8BMP280

Physical connections8 pinsPackage-specific numbering

Reference collection8 tables49 parameters & pin functions