LSM9DS1 datasheet(19/72 Pages) STMICROELECTRONICS

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LSM9DS1

LSM9DS1 functionality

3.1

Operating modes

In the LSM9DS1 the accelerometer and gyroscope have two operating modes available:

only accelerometer active and gyroscope in power down or both accelerometer and

gyroscope sensors active at the same ODR. Switching from one mode to the other requires

one write operation: writing to CTRL_REG6_XL (20h), the accelerometer operates in

normal mode and the gyroscope is powered down, writing to CTRL_REG1_G (10h) both

accelerometer and gyroscope are activated at the same ODR.

Figure 5 depicts both modes of operation from power down.

Figure 5. Switching operating modes

The magnetic sensor has three operating modes available: power-down (default),

continuous-conversion mode and single-conversion mode. Switching from power-down to

the other modes requires one write operation to CTRL_REG3_M (22h), setting values in the

MD[1:0] bits. For the output of the magnetic data compensated by temperature, the

TEMP_COMP bit in CTRL_REG1_M (20h) must be set to ‘1’.

3.2

Gyroscope power modes

In the LSM9DS1, the gyroscope can be configured in three different operating modes:

power-down, low-power and normal mode.

Low-power mode is available for lower ODR (14.9, 59.5, 119 Hz) while for greater ODR

(238, 476, 952 Hz) the device is automatically in normal mode. Table summarizes the ODR

configuration (ODR_G[2:0] bits set in CTRL_REG1_G (10h)) and corresponding power

modes.

To enable low-power mode, the LP_mode bit in CTRL_REG3_G (12h) has to be set to ‘1’.

Low-power mode allows reaching low power consumption while maintaining the device

always on, refer to Table 10.

LSM9DS1 数据表(PDF) 19 Page - STMicroelectronics