MP3398EGF-Z can not work in parallel mode

Lighting Solutions
1

The Gate of IC can not output but the VIN and VCC is ok. Do you usually know some reason can cause this issue？

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2

Hi Kevin,

Thank you for your question. It is possible that the IC has entered a latched protection state. There are four conditions that will latch the GATE off (with more details on page 12 of the datasheet here):

  1. Short-string fault: If a short-string condition persists for 10 ms, the fault string is marked off and disabled until VIN or EN restarts.

  2. Cycle-by-cycle current limit: When inductor current exceeds the limit, the IC latches off until the power resets.

  3. Short inductor/diode: If the current-sense voltage across R_SENSE hits the protection threshold for eight switching cycles, the IC stops switching and latches.

  4. Thermal shutdown: If the die temperature exceeds 130C the IC latches off until the power resets.

To clear any of these latches: Perform a full power reset by removing VIN for at least 1 second, then re-applying VIN and asserting EN > 1.5V.

If the GATE re-latches within a few cycles of power-up, the underlying fault is still present and must be repaired before normal operation can resume.

Please let me know if the issue persists after a full power cycle and fault check.

Thanks,

Mason