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TPSI3052-Q1: VDDP overvoltage and signal integrity

Dan Pearson
Prodigy 10 points

Part Number: TPSI3052-Q1
Other Parts Discussed in Thread: TPSI3052

Tool/software:

Hello,

We have the TPSI3052-Q1 designed into our product to drive a Mosfet in Three-wire mode. We have had a few instances where the the driver has failed with a short between VDDP and VSSP. Upon investigation, we observed that the VDDP voltage (referenced to VSSP) during operation ranges from 5.7V to 6.3V, which exceeds both the recommended operating conditions and the absolute maximum rating of 6.0V as specified in the datasheet. Additionally, we have captured distorted rising edges on VDDP during power-up, resembling switch bounce or ringing, which may be contributing to transient overvoltage conditions.

My question is, is the failure mode (VDDP–VSSP short) consistent with damage caused by exceeding the absolute maximum voltage rating and/or poor power-up signal integrity?

Driver circut below:

Thank you

  • 0
    TI__Expert 8771 points

    Hello Dan,

    Yes, this sounds like a damaged IC. I typically check the device's quiescent current and if that is off, then I know something is wrong. Maybe try adding a 5.1V Zener diode to help clamp the VDDP.

    Best regards, 
    Tilden Chen

    Solid State Relays | Applications Engineer

  • 0
    Prodigy 10 points

    Hello Tilden,

    Thanks for your response.

    Our circuit currently uses a 6V regulator to supply VDDP. To avoid a full PCB redesign, we are planning a straightforward component swap by adding a voltage drop diode to bring the voltage below the recommended maximum of 5.5V for VDDP. Although a Zener diode would offer tighter clamping, it would require layout changes we are trying to avoid.

    Do you think that operating above the 5.5V limit, specifically in the 5.7V to 6.3V range, along with input ringing, could plausibly have caused the TPSI3052-Q1 failure we observed, which resulted in a short between VDDP and VSSP? And does our proposed fix significantly reduce the risk of recurrence?

    Thanks for the help.

    Best regards,
    Dan

  • 0 in reply to Dan Pearson
    TI__Expert 8771 points

    Hello Dan,

    Thanks for your reply. Yes, your failure case sounds similar to my own testing when I have accidentally connected a 12V supply to the input and destroyed the device, resulting in Iq hitting the current limit.

    You have probably considered this already, but I would double check whatever diode you are considering to make sure it has the correct voltage drop at the TPSI3052 Iq. Or in this case, making sure the diode has 0.8V drop at 5 mA in order to drop 6.3V to 5.5 V.

    What is your application here? Will you need to pass any EMC testing?

    Best regards, 
    Tilden Chen

    Solid State Relays | Applications Engineer