Hello Team, We would like to confirm the current consumption of the LSM6DS3USTR while enabling the Accel+ Gyro Mode.

[PRaji.1]

We are in middle of our Production process and we are using your LSM6DS3USTR.

Here are the setup we have :

1. combo mode (i.e Accel+gyro)

2. ODR = Accel(26Hz) and Gyro(26Hz).

3. Input power supply = 1.8V

Currently, we are seeing a constant current pull off 460uA with a peak current of 1.392mA for every 38ms Approx. Can you confirm the above measurement which we are seeing? and it would be great if you recommend any other way to reduce the current pull down further.

Please find the attachment for your reference

[Eleon BORLINI]

Hi @PRaji.1​ , I assume you are reading the data with SPI or I2C protocol every 26Hz (i.e. 38ms), right? It seems that your measures are reasonable. To reduce this current consumption you should act on the communication event, for example reducing the SPI speed, or increasing the pullup resistors value in the I2C case. Which is your current communication protocol speed? Regards

[PRaji.1]

Hi Eleon,

Thanks for getting back to me.

Yeah we use SPI Protocol. The SPI Communcation speed is at 8MHz (Works well for all other ST Chips). Yeah, we are bit concerned about measures there because, the 1.392mA for every 38ms and 460uA is draining our battery as the sytem measure the Accel&gyro 24 x7 hrs.. The peaks go further down if we enable the Accelerometer alone mode. We are using NRF52 Power Profiler for current measurment protocol software and it has 77KHz Sampling rate. The above is the application circuit we use. Any recommendation on the application circuit is appreciated.

Thanks

Prakash Rajiah

Firmware Engineer

Shimmer Research Ltd

Dublin

Ireland

[PRaji.1]

HI Eleon ,

Just to make clear on the above, We are using FIFO mode . So we arent reading the data through SPI for every 38ms. We are only reading data through SPI, only at every 1.2s.

Thanks

Prakash Rajiah

[Eleon BORLINI]

Hi Prakash, so it seems that the current consumption goes higher while you are writing the FIFO every 38ms... But are you working in Normal Mode or High Performance mode (especially for the Gyro, if you wrote that >> The peaks go further down if we enable the Accelerometer alone mode)

A comment also on the connection, as reported in the datasheet application hints (p.41):

The SDx and SCx are connected to a fixed voltage, Vdd or GND, while you are leaving them unconnected. I'm afraid they could someway affect the overall current consumption...

Regards

[PRaji.1]

Hi Eleon,

Just to update on this. As you suggested, We have connected SDx to SCx to GND and we are still seeing the high current peak at every 38ms. Would it possible for your team to replicate the issue.

Our current setup we have is :

1. combo mode (i.e Accel+gyro)

2. ODR = Accel(26Hz) and Gyro(26Hz).

3. Input power supply = 1.8V

4. Normal Mode

Thanks

Prakash