BMA400 FIFO Low Power Issue

[fatihozen]

Hi,

I have Low Power MCU and I will work with small batteries. Power consumption is important. Now I am reading datas from BMA400's FIFO in every 5 seconds. I made ODR 50 Hz. I check fifo full interrupt every 200 ms and BMA400 is in normal power mode. My question is about consumption. How to reduce consumption of BMA400 with reading FIFO ? Another question is reading FIFO is the lowest consumption option ? I mean FIFO can only be read in normal mode and in normal mode it consumes more than other modes. I am reading datas in 8 bits resolution and from all axes(x,y,z). What do you suggest me ? 

[FAE_CA1]

Hi,

Thanks for your inquiry.

BMA400 FIFO works in normal mode at 3.5uA current consumption from 12.5Hz to 800Hz. You can refer to the attached PDF file for more information for your application.

Thanks.

[fatihozen]

Thank you so much for document, it is very useful. I want to know that is reading FIFO in normal mode every 5 seconds consumes less power or reading x-y-z axes datas continuously in sleep or auto low power mode during 5 seconds.

[FAE_CA1 · Accepted solution]

Hi,

BMA400 has low power mode at fixed 25Hz sampling rate that consumes less than 1uA. So it is lower power when you read BMA400 data at low power mode. When BMA400 is in sleep mode, there will be no measurement ongoing. This means that you cannot get BMA400 data in sleep mode.

Another way to save power is use BMA400 auto-low-power and auto-wakeup interrupt feature. This means that you don't need to read BMA400 data at all if there is no motion event happened. Please see the attached PDF for more information. You can save more power doing this.

Thanks.

[fatihozen]

Thank you, it seems it helps to solve my problem.I wonder, is there a URL I can reach all of documents(I mean more documents about BMA400) you sent in attachment ?