LIS2DH12 excessive current draw

[Rishi Shukla]

Posted on April 16, 2018 at 12:37

I am using LIS2DH12 on my custom designed board for a BLE application.

I noticed that the PCB had a huge current draw than expected and on further digging found the accelerometer to be drawing the excessive current while in Power Down mode. Thorough testing revealed that the SA0 line used to select I2C address was the root cause of this problem. Connecting SA0 to ground (GND) led to huge current draw. However, connecting SA0 to VDD (logic HIGH) solved the huge current draw problem.

Is this behaviour expected from the accelerometer? If yes, why? If not, what could be other possible factors leading to such behaviour.

Thank you.

#current-consumption #i2c-address

[Miroslav BATEK · Accepted solution]

Posted on April 16, 2018 at 13:21

Yes, this is expected behavior. The current is caused by internal pull-up resistor on SA0 pin.

There is a possibility to disable the internal pull-up in CTRL_REG0 (1Eh) register.

For more details please check the

http://www.st.com/resource/en/datasheet/lis2dh12.pdf

.

[Rishi Shukla]

Posted on April 26, 2018 at 14:14

Tested and works.