2020-07-22 04:15 AM
2020-07-22 06:52 AM
Hi @OWigd.1 , it's not a totally safe condition leaving Pin8 unconnected, since it is by default an input high impedance node. Is it working I2C only sometimes or always? Regards
2020-07-22 07:36 AM
2020-07-22 01:40 PM
Hi Eleon,
Thanks for your answer.
Yes, i know it not "totally safe"
But is there an explanation why it works well for me ( I2C) and never wakes up SPI mode ?
Are you familiar with the HW design of pin8 (CS) input ?
Thanks
2020-07-22 01:51 PM
Hi Eleon,
Thanks for your answer.
Yes, i know it not "totally safe"
But is there an explanation why it works well for me ( I2C) and never wakes up SPI mode ?
Are you familiar with the HW design of pin8 (CS) input ?
Thanks
2020-07-23 09:10 AM
Hi @OWigd.1 , what I understood from our experts is that the CS is high impedance to be properly driven but the device sets internally a status (i.e. like an internal pull-up) to prevent a wrong or unknown startup status in the case the pin is not connected. Btw, I confirm again that this pin should be connected at least to the application processor to be able to manage it in a known status. Regards
2020-07-24 12:50 AM
Thanks Eleon,
This is important information for us.
So, to my understanding , If Pin8 ( CS) left open (I know I should be tied high for I2C)
LIS3DH shall establish I2C communication regardless ( this is what we actually see)
Could you elaborate more about : "but the device sets internally a status (i.e. like an internal pull-up) to prevent a wrong or unknown startup status in the case the pin is not connected"
A more technical / design explanation ( from the experts , chip designer) would be appreciated .
Regards and many thanks
Oded