This product is a fully assembled and tested AHRS and barometric pressure altitude sensor.
- The “standard” GY91 sensor contains both, the AHRS MPU9250 as well as the pressure sensor BMP280 on one board and is therefore a bit more compact
- The newest generation contains a standalone AHRS MPU9255 sensor. Hence the pressure sensor BMP280 is soldered under the AHRS board.
This board does not contain a fan control, because the transistor used for the control increases the antenna noise. When using this board you have the option to connect the fan permanently to either 3.3V or 5V.