• State TI Thinks Resolved
  • Replies 5 replies
  • Answers 2 answers
  • Subscribers 32 subscribers
  • Views 110 views
  • Users 0 members are here
Support feedback
Options
Options
Related

DCA1000EVM: DCA1000EVM failure – Board overheating

Antish Antony
Prodigy 70 points

Part Number: DCA1000EVM

Hi TI Team,

I am looking for some guidance regarding an issue I am seeing with my DCA1000EVM. 

Issue

  1. The board is connected to a 5 V DC adapter, and the DCA1000EVM board and the LM26400YMHX (U1) regulator becomes too hot within a short time. We have been using this board and was working properly until last day. 

    I am sharing my observations below.

    1. I have never connected a 12 V supply to the DCA1000EVM. The board has always been powered using  5 V DC barrel jack adapter. 
    2. The below point shows a short. 

    image.png

    Multimeter observations (board powered OFF)

    The following measurements were taken with the board powered off:

    Component Continuity to GND Resistance across component
    F1 Both ends show continuity to GND. ~0.2 ohms
    D16 Both ends show continuity to GND. ~8.6 ohms
    C112, C126 Both ends of both capacitors show continuity to GND. ~8.5 ohms each
    C38, C39 Both capacitors show continuity to GND. ~6.2  ohms each
    C36, C37 Both capacitors show continuity to GND. C36: ~70.7 ohms, C37: ~60.4 ohms

    Based on the above observations, could you please let me know if there are any additional measurements or troubleshooting steps that would help identify the root cause of this issue?

    Also, does this appear to be a potentially repairable issue ?

    Any guidance or suggestions would be greatly appreciated. Thank you!

  • 0
    TI__Intellectual 2666 points

    Hi,

    Please check out the following E2E : 

    1. DCA1000EVM: DCA1000EVM: Repeated failure - L4 component overheating and Ethernet connection failure

    2. DCA1000EVM: Flashing LEDs. Board not coming out of reset. Cannot connect to any power source. Is my board broken?

    Some of the reasons for this short could be : 

    • Measure resistance directly at the output pins of U1 for each output channel to determine which output rail carries the short
    • Measure resistance on both sides of L4 to ground. If one side shows significantly lower resistance, the short is downstream (likely Ethernet PHY or 1.1V LDO)
    • Visual inspection around the short area could also be another cause for this short to happen

    Thanks, 

    Ahanaf

  • 0 in reply to Ahanaf Ahmed
    Prodigy 70 points

    • I performed the requested resistance measurements.

      • Resistance across SW1: 6.2 Ω

      • Resistance across SW2: 59 Ω

      I also measured the resistance to ground on both sides of L4:

      • One side: 3.02 kΩ

      • Other side: 3.05 kΩ

      Additionally, I have attached two images from my board:

      1. The U1 voltage regulator.

      2. The area containing U11 and U10.

      On U11, I noticed a small mark on the IC package. Could you please let me know if this appears to be normal, or could it indicate damage?







      I am based in Bengaluru, India. If additional troubleshooting is required, is there a service center or repair facility where I can send the board for evaluation? If repair is possible, please let me know the process and any associated requirements.



  • 0 in reply to Antish Antony
    TI__Intellectual 2666 points

    Hi, 

    Based on the resistance value that you shared the DCA1000 EVM that you are using has a short in 2.5V power rail. Both resistance value between SW1/2 is really low and indicates shot circuit. The low resistance values across SW1/2 indicates a shorted downstream  and components are drawing excessive current through L4, causing thermal stress or overheating. The first E2E that I shared has the exact same issue. One last thing we can do to confirm this, please measure the 2.5V rail and you should see voltage value less than 2.5V which would indicate that the short circuit we are seeing from this resistance measurement. 

    Did you buy this EVM from TI.com?

    Thanks, 

    Ahanaf 

  • 0 in reply to Ahanaf Ahmed
    Prodigy 70 points

    Hi,

    Thank you for your help and guidance so far.

    I will check the 2.5V rail voltage and get back to you with the measurements.

    We did not purchase the DCA1000EVM directly from TI. The board was procured through a third-party supplier in India around July 2024. It has been functioning normally for nearly two years and has only recently started showing the overheating. 

    Is there any support available through TI India for troubleshooting, evaluation, or repair? Any guidance on the available options would be greatly appreciated.

  • 0 in reply to Antish Antony
    TI__Intellectual 2666 points

    Hi, 

    Yeah sure no worries! 

    As you did not buy this directly from TI for any replacement please contact the third-party vendor. 

    We do not have a support team for this device in India. Sorry. 

    Thanks, 

    Ahanaf