2018-01-08 07:39 AM
Hello,
I am using IIS2DH to work for my application. But the problem rises when I measure the current it is consuming. At 25Hz with 40ms INT2 duration and Low Power Enabled with all axis, I am observing a current a current of 500uA which is not according to what mentioned in the data sheet of IIS2DH. The configuration is shown below:
CTRL_REG1: 0x3F
CTRL_REG4: 0x20
CTRL_REG6: 0x20
INT2_CFG: 0x04
INT2_THS: 0x05
INT2_DUR: 0x01
The above configuration works perfectly for my application. However, it is consuming a lot of current. Am I missing something? Please help.
Also, could anyone explain to me as to how BOOT_I2 bit on CTRL_REG6 work ? what is its function? Where can i find information about it?
#iis2dhSolved! Go to Solution.
2018-01-09 01:10 AM
Yes, there is. If you connect the SA0 pint to GND there is additional current consumption cause by internal pull-up on this pin. So you can connect this pin to VDD_IO and you will rid of this current.
2018-01-08 07:47 AM
Concerning the current consumption, can you please share the schematic?
The BOOT_I2 bit in CTRL_REG6 allow to see boot status on the INT2 pin, basically if you enable this bit the INT2 pin will be high during sensor boot-up and goes low after that.
2018-01-08 10:07 AM
Hello Sir,
There is not much in the schematic. I just have the STEVAL-MKI168V1. connected to TI-Launchpad CC2640 . I have the launchpad powered on using a battery. The battery +ve terminal is connected to one terminal of the Ammeter(uA) and from the other terminal it is connected to the Launchpad. The Launchpad has 3.3V port from which the STEVAL-MKI168V1 is connected. The TI - Launchpad configures the accelerometer and enters shutdown mode.
Regards
2018-01-08 10:41 AM
Can you please measure the current consumption only of the sensor, connect the ammeter between 3.3V port on Launchpad and the VDD + VDD_IO of the sensor.
According to your description it seems you are only assuming the current is flowing into the sensor and the current consumption of the Launchpad is negligible.2018-01-08 10:56 AM
Hello Sir,
Thank you for the quick reply. I did the changes as you mentioned. I am getting now around 100uA as the current. Is there something else that I am doing wrong here ?
Regards
2018-01-09 01:10 AM
Yes, there is. If you connect the SA0 pint to GND there is additional current consumption cause by internal pull-up on this pin. So you can connect this pin to VDD_IO and you will rid of this current.
2018-01-09 09:34 AM
Hello Sir,
It is consuming upto 4uA now. Thank you for helping me.
2018-01-09 08:58 PM
Hi Miroslav, on my board, the SA0 pin is floating which means there is no connection either to VCC or GND. So, is it affect current consumption or is it fine? Can you please provide comment on this query.
2018-01-10 01:49 AM
If the SA0 pin is let floating there won't be any additional current through internal pull-up, but this is not recommended configuration. The pin should be polarized (connected either to VDD_IO or to GND).