The BME280 is an APSM (Advanced Porous SiliconMembrane) process digital digital composite sensor in a small package with low power consumption, which measures ambient temperature and humidity and atmospheric pressure.
It is backward compatible with the BMP280, and the barometric pressure temperature register control and data readout operate in the same way.
The moisture-sensitive element has fast wake-up and response times, high accuracy and a wide temperature operating range.
The barometric pressure sensitive element is a piezoresistive low noise high accuracy high resolution absolute atmospheric pressure sensing element; and
The temperature sensing element is a low-noise, high-resolution element, and the temperature value is self-correcting for humidity and barometric pressure with temperature compensation.

Operating Voltage:BME280(1.7~3.6VDC)BMP280(5V DC)
Temperature Measurement Range:0℃~65℃
Temperature Measurement Error:±0.5℃ MAXS1℃;Resolution 0.1℃.
Relative Humidity Measurement Range:0%~100
Humidity Response Time:>1s
Relative Humidity Measurement Error:2%
Humidity hysteresis:-1%;Resolution 0.8%
Barometric pressure measurement range:300~1100hPa
Barometric pressure measurement error:±1hPa Resolution 0.18Pa
Digital interface type: I1C (from the mode 3.4MHz) or SPI (3-wire or 4-wire from the mode 10MHz)
Dimensions:15.4mm(L)*11.6mm(W)*2.4mm(H)
With M3 fixing screw holes for easy installation and fixing.

VCc: Power Positive
GND: Ground
SCL: 12C/SPI serial clock line
SDA: 12C serial data line
3-wire SPI serial data input/output port
4-wire SPI serial data input port
CSB: chip select pin, connect high (default) for IC communication interface
Low level is SPI communication interface
SDO: 12C address select bit 4-wire SPI serial output port