• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 80 subscribers
  • Views 1123 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

MSP430F5659: MSP430F5659 reserved pins

Nobuyoshi Arai44
Expert 2575 points
Part Number: MSP430F5659


Hello TI Experts,

 

I have got a question from the customer about the reserved pin of MSP430F5659.

Would you please check the following question and give any comment or your opinion?

 

[Question]

They are using the MSP430F5659IZQWR (BGA type) that has 11 Reserved pins.

(E5,E6,E8,F4,F5,F8,G5,G8,H5,H8,H9)

It is written in the datasheet like below;

"Reserved BGA package balls. It is recommended to connect to ground (DVSS, AVSS)."

Thus, they are connecting 11pins to GND. But if these pins are not connected to GND due to some reasons like soldering defect or implementation failure, what kind of problem can be considered?

I know it is difficult to mention what may occur if these pins are not connected. But they want to know what kind of effect there is.

 

[Background]

They are seeing the problem that the RTC calendar outputs some strange values.

I had already posted the following e2e thread below but this has not been solved yet.

https://e2e.ti.com/support/microcontrollers/msp430/f/166/t/675454

 

This question may not be related with the problem above. But they are asking this question.

So, if you can give any comment to this question, it would be helpful.

 

Thank you for your comment.

 

Best Regards,

 

Nobu Arai

  • 0
    TI__Genius 14875 points
    Hi Nobu,
    I can ask design, but I'm not sure what they will come back with. I don't have visibility to what those pins are connected to so I don't know. Bottom line is that if the datasheet recommends connecting them to ground, it is best to do so.
  • 0 in reply to Cameron LaFollette
    Expert 2575 points

    Hello Cameron,

     

    Thank you for your comment.

     

    I understand your comment and have basically asked our customer to follow the recommendation in the datasheet.

    But if you can get any feedback from your design team, it would be helpful.

     

    Best Regards,

    Nobu Arai

  • 0 in reply to Nobuyoshi Arai44
    TI__Genius 14165 points

    Arai, Cameron,

    I checked the package details and can confirm the corresponding balls are really not connected to the device.
    Means not connecting them to GND should not have an impact to the RTC functionality however bringing floating material to fixed potential is always better than letting it float that's why we have this recommendation in the datasheet.

    Best regards,
    Dietmar

**Attention** This is a public forum