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TPS62290: TPS62290 Heating and Short Issue

Part Number: TPS62290

Hi, I am using TPS62290DRVT regulator IC for converting 5V to 3.3V in my project. I have the following issue. This IC often gets shorted & results in huge dissipation of heat in my project's PCB. The SW pin is the one that gets shorted with ground pin. This short/heating issue occurs occasionally and whenever I replace it with a new IC of the same part the board works fine again. But after some time or after so many uses, the problem recurs even with new ICs. Could anyone provide me a solution for this issue? I also need an explanation why this problem occurs only occasionally and not everytime. Kindly reply me as soon as possible.

  • Hello,
    in order to support you I need more information. If for you is ok, you can post the schematic and layout or you can forward to my personal email. I will be also glad to receive other details concerning your application.
  • Alfonso Furio said:
    Hello,
    in order to support you I need more information. If for you is ok, you can post the schematic and layout or you can forward to my personal email. I will be also glad to receive other details concerning your application.

    Hi, please find the attached power section schematics of my project for your reference. I am using a USB 3.0 host port & USB Type-C receptacle in my board. This board is a bus-powered one and hence the input 5V comes from the USB 3.0 host port in a PC. From this 5V input, I am using various regulators, referenced as U9, U10, U11, U12, from TI to generate 3.3V, 1.2V, 1.8V, 2.7V respectively. The above-mentioned problems are with U9 IC, which is used to convert 5V to 3.3V. This U9 regulator often gets shorted(SW & GND) and results in enormous heat dissipation too. Kindly respond to this issue as soon as possible.Power Regulators Schematic.pdf

  • Hello,

    I check your schematic and I can suggest to follow our documentation. It is not recommended to use ferrite beads at the input, in this way you can seriously damage the device by an overvoltage (considering also the 5V at the input). Further details can be found also in this document:www.ti.com/.../slvu217.pdf

  • If placing ferrite bead at the input side is the problem, then should the input ferrite beads in other regulator ICs such as U10, U11 & U12 also be removed? And could u tell me the reason why the other ICs are not getting affected inspite of having the ferrite beads? Especially U10 IC since it also has 5V input! All the Regulator ICs are from TI only. Kindly reply me as soon as possible.
  • Hello,
    In your schematic, different IC are combined with different ferrite beads that have tolerances, so it is not easy to predict the behavior. I can suggest a small experiment; you can change the ferrite bead with a jumper or a 0 Ohm resistor, replace the failing IC and see if the problem appears again. It is highly probable that the device was damaged by an electrical overstress. This ferrite bead changes the transfer function (it acts as an inductance) at the input and it is possible that some noise components (due to the shape of the current in the high-side mos) were amplified creating an overshoot at the input.
  • Thank you for your reply. I already performed the experiment you mentioned. I replaced the ferrite bead with 0 Ohm resistor for the defective IC (replaced the defective IC too). So far no issues in the board and it successfully passed a 12 hour long-run test. But even the previous boards have successfully passed 24 hour long-run tests with the ferrite beads mounted. So I cannot come to a conclusion that the mentioned issue has been completely solved. Could you confirm whether the ferrite bead is the only problem that caused the issue I mentioned? Kindly enlighten me, if there are any other discrepancies.

    Thanks & Regards,
    Muhammed Junaidh M