Accelerometer LIS2DH12 connected to DA14585 BLE and external memory AT25XE011 pulling down the power supply and SPI lines

[Anushiya Kannan]

Posted on May 18, 2018 at 04:50

DA14585 BLE is connected to accelerometer LIS2DH12 sharing the SPI lines with external flash memory AT25XE011. There are two issues I am facing.

1) When all devices are connected to the 3.2V power supply rail, LIS2DH12 pulls down the power supply to ~1.6V. When the power supply to LIS2DH12 is disconnected, the rest of the board get the power supply of 3.2V. Why LIS2DH12 causing this effect?

2) Even when the supply voltage of LIS2DH12 is removed,

LIS2DH12

is pulling down the shared SPI lines SD0/SA0 and SPC. I read in another question at this site about changing the register value

CTRL_REG0 (1Eh)

to

disable the internal pull-up

 at SA0/SD0. Is it possible to prevent this happening at the power up stage? 

Thank you

Anushiya

#da14585-with-lis2dh12 #lis2dh12

[Miroslav BATEK]

Posted on May 22, 2018 at 21:05

Are you sure that you schematic and PCB layout or soldering is correct, according to your description I think it is not.

There is no reason why the LIS2DH12 should pull down the power supply.