• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 31 subscribers
  • Views 239 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.

TM4C1294KCPDT: About Vin_GPIO

Kurumi Hasegawa
Expert 7991 points

Part Number: TM4C1294KCPDT

The datasheet states the absolute maximum rating of input voltage (Vin_GPIO) is 4V, (not VDD+**V), in table 27-1.

 

Does it mean situation like instantaneous voltage below 4V was applied to I/O ports before power was supplied to the micro controller is acceptable?  

Also, does this Vin_GPIO include input/output ports which are not set as GPIO (ex. AD port)?

  • 0
    TI__Guru 72500 points

    Remember that absolute maximum is the value which exceeded may cause permanent damage to the part. The part will likely not operate properly at those levels. 

    Kurumi Hasegawa said:
    Does it mean situation like instantaneous voltage below 4V was applied to I/O ports before power was supplied to the micro controller is acceptable?

    You must also be below the absolute maximum current for that pin to be sure damage does not occur. I would not say acceptable because the device may be powered through the GPIO pin and its operation would be erratic. 

    Kurumi Hasegawa said:
    Also, does this Vin_GPIO include input/output ports which are not set as GPIO (ex. AD port)?

    Yes, but again this does not imply proper operation.

  • 0 in reply to Bob Crosby
    TI__Expert 7991 points

    Hi, thank you a lot for the reply.

    So, is it OK (or will not break the device) to apply voltage below 4V to GPIO pin without supply voltage?

    I mean, usually voltage rating is described as VDD + xV, but for this device it is described as 4V (fixed value).

    It bugs me a little.

    Sincerely,

    Kurumi Hasegawa

  • 0 in reply to Kurumi Hasegawa
    TI__Guru 72500 points

    I cannot say "OK", I can merely repeat what is in the datasheet: "The maximum ratings are the limits to which the device can be subjected without permanently damaging the device. Device reliability may be adversely affected by exposure to absolute-maximum ratings for extended periods."

  • 0 in reply to Bob Crosby
    TI__Expert 7991 points

    I understand. Thank you a lot