• State
  • Locked Locked
  • Replies 6 replies
  • Subscribers 62 subscribers
  • Views 735 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.

TPS650830 FBVR5P/FBVR5N unconnected

Antony Lin
Genius 13480 points
Other Parts Discussed in Thread: TPS650830

Hi,

Customer would like to know the impact if  FBVR5P/FBVR5N are unconnected.  only VR5 not work?  Or the chip could be damage?

Thanks!

Antony

  • 0
    TI__Intellectual 1990 points

    Hi Antony,

    Thanks for the post! If a regulator is not to be used on TPS650830, in this case VR5, the following connections should be made in order for TPS650830 to operate properly and prevent damage to the device.

    • ENVR5 to GND

    • VINVR5 to VIN

    • PGVR5 to float

    • FBVR5P&N to GND

    • PGND to GND

    • SWVR5 to GND

    • DRVH&L to float

    • BOOT to float

    • RLIM to GND

    Let me know if there are any questions. Thanks!

    Regards,

    Paul Kundmueller

  • 0 in reply to Paul Kundmueller
    TI__Genius 13480 points

    Hi Paul,

    Thanks for the reply.  I think i didn't put the questions clearly.  

    The situation now is, customer is using VR5 on their board and connect related pin correctly   They just want to know better what will happen to our chip when FBVR5P/FBVR5N are unconnected by accident.  Will is damage our chip?

    Thanks!

    Antony

  • 0 in reply to Antony Lin
    TI__Intellectual 1990 points
    Hi Antony,

    As long as ENVR5 is GND'ed then there should be no issue if FBVR5P/FBVR5N are unconnected by accident. Let me know if there are any other questions. Thanks!

    Regards,

    Paul Kundmueller
  • 0 in reply to Paul Kundmueller
    TI__Genius 13480 points
    Hi Paul,

    For customer's situation, ENVR5 is actually at high level and VIN is supplied correctly. So, they want to know if our chip would be damaged or not if FBVR5P/FBVR5N are unconnected under such situation.

    Thanks!

    Antony
  • 0 in reply to Antony Lin
    TI__Intellectual 1990 points
    Hi Antony,

    Ah I see, sorry for the confusion. If FBVR5P/FBVR5N are left unconnected by accident, two scenarios may occur, 1, the overvoltage power good will trip causing the regulator to be shut off (30us of deglitch) or , 2, the controller will try to continuously pump the output voltage higher and higher causing the device to rail out which would damage the device. It would be a race conditions between the two of these scenarios, I would expect for the overvoltage power good to kick in after 30us before scenario 2 happens but either of the scenarios could potentially occur. Let me know if there are any questions. Thanks!

    Regards,

    Paul Kundmueller
  • 0 in reply to Paul Kundmueller
    TI__Intellectual 1990 points
    Hi Antony,

    Another note, when a rail is powered up, power faults are initially masked for 10ms. In this case the device or system would probably most likely be damaged as the output of the rail would be driven to VIN before a power fault shutdown would be issued. Let me know if there are any questions. Thanks!

    Regards,

    Paul Kundmueller