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FPode.1
Associate
Sep 26, 2020 11:32 AM UTC
Solved

Hi there, We just realized we made an error in the schematic and we would like some advice from ST. the LIS331 has 2 reserved pin (10 and 15), we erroneously have connected the pin 15 to GND. would this stop the LIS331 to work? Thank you, Francesco

Hello there,

0693W000004HCBLQA4.png

This topic has been closed for replies.
Eleon BORLINI
Eleon BORLINIBest answer
ST Employee
Sep 29, 2020 10:18 AM UTC

Hi @FPode.1​ ,

I unfortunately don't have good news about your question... the PIN 15 is used for programming and erasing the internal flash memory, since the HV levels needed for this purpose are generated using this supply. From internal check, I can say you that it is mandatory to keep the pad level over 1.8V in any functional mode. Max voltage on this supply is 13.5V. When not used for programming purpose this pad must be kept to power supply (VDD).

If you could invert the polarity of the reserved pins, i.e. both PIN10 and PIN15 to VDD level, things may be more safe for a standard working mode of the device...

-Eleon

3 replies

FPode.1
FPode.1Author
Associate
Sep 28, 2020 10:28 AM UTC

Hello,

can anyone from ST answer the question?

We acknowledge that we made an error, we are trying to understand if we can use the PCB that we have just received.

Thank you!

Francesco

Eleon BORLINI
Eleon BORLINIBest answer
ST Employee
Sep 29, 2020 10:18 AM UTC

Hi @FPode.1​ ,

I unfortunately don't have good news about your question... the PIN 15 is used for programming and erasing the internal flash memory, since the HV levels needed for this purpose are generated using this supply. From internal check, I can say you that it is mandatory to keep the pad level over 1.8V in any functional mode. Max voltage on this supply is 13.5V. When not used for programming purpose this pad must be kept to power supply (VDD).

If you could invert the polarity of the reserved pins, i.e. both PIN10 and PIN15 to VDD level, things may be more safe for a standard working mode of the device...

-Eleon

FPode.1
FPode.1Author
Associate
Sep 29, 2020 10:22 AM UTC

Hi Eleon,

thank you for your time...

We will fix and respin the PCB.

Kind regards,

Francesco