ADXL345 3-Axis Digital Acceleration of Gravity Tilt Module (GY-291)

Introduction

ADXL345 is a low-power consumption triaxial accelerometer with tiny and thin appearance. It can measure the acceleration that reaches ±16 g with high resolution (13 bits). The output data mode of ADXL345 is 16-bit binary complement that you can access through SPI (line 3 or line 4) or I2C digital interface.

Application

Mobile Phone
Medical instrument
Game and pointing device
Industrial instrument
Personal navigation device
HDD Protection from falling
Screen flip on tablet computer

Main Features

Type: GY-291
Chip: ADXL345
Power Supply: 3~5V
Communication Mode: Standard IIC/SPI communicating protocol
Measuring Range: ±2g±16g
3 axis, ± 2g/ ± 4g/ ± 8g/ ± 16g

Introduction of Pins

Introduction of Pins
GND	Cathode of the power supply.
VCC	Anode of the power supply is connected to 3-5V.
CS	Chip select.
INT1	Interrupt the output 1.
INT2	Interrupt the output 2.
SD0	Serial data output (SPI 4 wire), spare I2C address choose(I2C).
SDA	Serial data (I2C), Serial data input (SPI line 4), Serial data input, output(SPI Line 3)
SCL	Serial data (I2C), Serial data input (SPI line 4), Serial data input, output(SPI Line 3)

Principle

ADXL346 is a complete 3-axis acceleration measurement system. Its selectable measurement ranges can be ±2 g, ±4 g, ±8 g or ±16 g. The component can not only measure the dynamic acceleration cased by movement or shock, but the static acceleration, such as gravity acceleration; so it can work as a tilt sensor.
The sensor applies micromachining structure of polycrystal surface and puts it on the top of the wafer. The polycrystal spring hangs over the surface structure of the wafer and supplies the resistance cased by the acceleration.
The independent fixed board of the differential capacitance is combined with the active mass connection board and it can measure the deviation of the structure. Acceleration gives the mass detection block a deflection and lets the differential capacitance be out-of-balance. So the output range of the sensor is in proportion to the acceleration. Phase sensitive demodulation uses and ascertains the range and polarity of acceleration.