ULP mode LSM6DS032 configuration procedure

[bimalpaneru]

Hi all,

Been trying to use the ULP mode on LSM6DS032 with following steps.

1. Setting XL to Power down mode by setting XL_ODR bits to 0b0000  of CTRL1_XL register.

2. Set I3C_DISABLE to 1 of  register CTRL9_XL. // Not sure if this is necessary

3. Power down the gyroscope by setting ODR_GY bits to 0b0000 of reg CTRL2_G .

4. Set XL_HM_MODE = 0 of reg CTRL6_C (15h) // ref Sec 6.2.1 of datasheet.

5. Finally, XL_ULP_EN bit to 1 in reg CTRL5_C (14h).

Here is the actual problem, considering above steps to be correct for ULP use,
the setup I have got has no significant difference in current consumption with any of the modes, be it ULP or power down or normal or low power..

The sleep current for the my setup when IMU is turned off with a hard switch is ~0.6mA. However, the sleep current is ~1.2mA in each of the modes with IMU is powered on. I need IMU to be waking interrupt for whole of my system.

This seems very odd as the IMU is supposed to have consumption in few uA range as I am getting almost 600uA in any of the XL modes.

I have had a post  regarding this but there was no any further progress on the thread.
Also below is the hardware connection for reference, v_accelerometer is a MCU digital pin used for powering the IMU.
Operation voltage is 3.3V

I would really appreciate any suggestion/help on this.

Thanks in advance!

[Federica Bossi]

Hi @bimalpaneru ,

In power down I measure about 3 uA as reported in the datasheet.

Referring to the datasheet, the output data rate (ODR_XL) bits of CTRL1_XL register, the ultralow-power enable
(XL_ULP_EN) bit of CTRL5_C register and the high-performance disable (XL_HM_MODE) bit of CTRL6_C
register are used to select the output data rate and the power mode of the accelerometer. So the writings should be:

80h in register 14h

10h in register 15h

50h in register 10h (if you want an ODR of 208Hz)

Hope this helps.