12.2 Architecture of BME280 Sensor Module
BME280 is a 3.3V sensor. Therefore, one must use level sifters (5V/3.3V/5V) to operate it with Arduino UNO/MEGA/NANO. The sensor can be directly connected with Arduino DUE which is a is 3.3V device.
1. The BME280 Sensor MODULE contains the following three sensing elements:
Fig-12.9: 3.3V operational voltage BME280 sensor (2.5 mm x 2.5 mm x 0.93 mm)
(1) Temperature Sensor
(2) Pressure Sensor
(3) Humidity Sensor
(4) Architecture
Figure-12.9: Architecture of BME280 3.3V Sensor
(5) (a) Register Set
Figure-12.10: Register Set of BME280 Sensor
(b) Expanded view of Calibration Coefficient Registers
Figure-12.11: Expanded view of calibration coefficient registers
2. (1) The BME280 Sensor Module has 8 pins (Fig-7) with signal signatures as described in Fig-12.10:
Figure-12.11: Pins of BME280
(2) Pin Connection Options of BME280
Figure-12.12: Table showing pin connection options
3. (1) 3.3V BME280 Sensor Breakout Board without on-board Level Sifters and Voltage Regulator
Figure-12.13: Breakout board without level sifter
(2) 4-Wire SPI Port Connection with 3.3V BME280 Sensor Breakout Board using External Level Sifters
Figure-12.14: 4-Wire SPI Port connection of Fig-9 breakout board
(3) I2C Bus Connection of 3.3V BME280 Sensor Breakout Board with External Level Sifters
Figure-12.15: I2C Bus connection of 3.3v breakout board
4. (1) 5V BME280 Sensor Breakout Board with on-board Level Sifters
Figure-12.16: I2C bus breakout board with level sifters
(2) I2C Bus Connection with 5V BME280 Sensor Breakout Board using on-board Level Sifters
Figure-12.17: Connection diagarm between 5VBME280 Breakout and UNO using I2C Bus