• State Resolved
  • Locked Locked
  • Replies 6 replies
  • Subscribers 81 subscribers
  • Views 1049 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.

TMS320F28335: F28335 control card LD3 lights up red

chen ssu jung
Prodigy 50 points

Part Number: TMS320F28335

My chip is f28335, although the program can be programmed, but LD3 lights up red and the chip temperature is 176°F (80°C).

Although the chip can be programmed normally, the LD3 lights up in red, and the chip is so hot that the finger cannot be stayed.
What is the problem? Is my chip broken?

  • 0
    TI__Mastermind 30581 points

    Hello,

    It's hard to tell from the picture, but the boards look a little dusty. Have these been in storage for a long time? Where the boards working recently? Do you have more than one controlCARD? If so, does the other one work ok?

    I would recommend you remove the controlCARD from the docking station, then verify the docking station is working correctly. With the controlCARD removed, you can power the dock and check voltage levels on the dock to make sure they are working correctly.

    The LED2 and LED3 are controlled from GPIO pins on the MCU. If the code running on the MCU is not controlling the GPIOs, then the GPIOs are likely set to input. The buffer U3 on the board may have its output set to LOW which will turn on the LEDs.

  • 0
    Prodigy 50 points

    The circuit board is clean. The quality of the circuit board makes it look dirty. The circuit board is working in a clean laboratory. I have two control cards, and the other one is not like this, so I suspect that there is a problem with this control card!

    After the control card is taken out from the docking station, the input voltage of the docking station 5 voltage is correct

    The code running on my MCU does not control GPIO34, how can I set it to high?

  • 0 in reply to chen ssu jung
    TI__Mastermind 30581 points

    Thanks for the clarification. It would appear that there is a power to ground short on the controlCARD, likely inside the F28335 MCU. You could check the temperature of the 3.3V LDO (U2) on the board to see if it is also hot (or hotter). These types of failures can be caused by ESD or electrical over stress (EOS) on the device pins. 

  • 0 in reply to Gus Martinez
    Prodigy 50 points

    I use the thermal imager Fluke Ti32, the 3.3V LDO (U2) does not generate heat, and the temperature is room temperature.

    What other places can I check?

  • +1 in reply to chen ssu jung
    TI__Mastermind 30581 points

    I think the image is pretty clear: the MCU is the only IC heating up and is likely damaged.