The reason why MPM3515GQVE-AEC1-Z is burning

Integrated Inductor Power Modules
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I’m planning to use the MPM3515GQVE-AEC1-Z in a new design, configured for a 5V output voltage from an input that ranges from 8V to 24V (supplied through a connector and cable). My load is around 600mA to 1A.

Before I commit to this part, I came across the forum thread “MPM3515GQV is burning” from user “vsousa”, where the module was failing short-circuit at inputs above 20V even with the datasheet-recommended components. From that thread, the fixes that worked were a larger input capacitor (100uF), a higher EN/SYNC pull-up resistor (240k), and input/output Zener clamping. That’s why I felt a necessity to ask below questions.

My questions :

  1. Is this failure fully explained by hot-plug input voltage overshoot exceeding the 36V rating, or was there another root cause? I want to understand what actually damaged the part. Should I use 100uF capacitor although datasheet says 4.7uF is enough?
  2. How should I size the EN/SYNC pull-up resistor for a 8-24V input range so the pin current stays within limits at 24V while still enabling at 8V?
  3. If I follow these recommendations, can I use this part with confidence, or is there a reason to prefer a different module for a cable-fed wide-input rail?
  4. Are there evaluation boards, reference designs, application notes, for the MPM3515 that show the recommended input stage ( specifically the TVS standoff/clamp rating and the bulk input capacitance value I should design for ), input filter and layout for this kind of application?
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Hi,

Welcome to the MPS forums.

Here are the following responses to your questions.

  1. The root cause issue was not identified as the user “vsousa” made the changes that addressed the issue on their end. Are there any schematics you are able to share? Each schematic and test layout are different and the issue that they encountered may not be seen in your testing. If you would not like to post schematics on the forums, I can reach out via email. I would try the 4.7uF and 0.1uF capacitors recommended in the datasheet and should the issue happen to you as well, consider switching to the 100uF capacitor to address the issue.
  2. The datasheet specifies that the EN/SYNC current be limited under 100uA and that the typical EN/SYNC input current is 5uA. Utilizing the equation provided in the datasheet for the pullup resistor, a value of 175k will limit the current under 100uA at 24V and provide a current of 8.57uA when at 8V which is above the typical 5uA EN/SYNC input current needed to enable.
  3. This module meets your required specifications of and 8-24V input, 5V output, and 600mA to 1A load and therefore can be used in this application.
  4. There is an evaluation board available for purchase. Additionally, on page 16 of the datasheet there are PCB layout guidelines along with some example application schematics on pages 18-20.

Feel free to reach back out with any further questions.

  • Zachary