MP5030 Overvoltage

DC-DC Power Converters
1

Hi,

I’m using the MP5030 for an application that is only 5V. I have connected everything as per the reference design however I have left the adj pin floating as there is no need to change the input voltage. When the MP5030 is operating normally below 5.5V the device has a small quiescent power draw (uA range) but when I go above the 5.5V it starts to draw over 75mA.

  1. Why has the current consumption increased so much? It says in the datasheet that the IN and OUT pins are 16V (absolute maximum)

  2. Why is the test pin tied to VBUS when VBUS can be 3-12V for QC 3.0. The datasheet does not say that this pin is 16V tolerant although I have tried to limit with a zener to fix 1.

2

It would appear that there is a 100R resistor that is engaged in the event of an overvoltage. Is there a time out if the device becomes too hot? Seems to be engaged even up to 14V which is a recommended input voltage.

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3

Hi @william.schofield,

I believe the extra current is due to ADJ pin left floating.
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When the silicon die temp exceeds 150C it shuts down. When the temp falls below 125C, it is enabled again.

I hope this helps.

Thank you
Saurabh