LM5116: The MOS burnout after LM5116MH/NOPB power on

Hi 

MOSFET can be damaged by either over-temperature or an over-voltage.

Please let me know the test conditions in detail for more investigation. 

-Eric Lee 

There are two cases of burnout: 1. No load, MOS burnout at the moment of power-on; 2. No load, the MOS is burnt out within a few minutes after power-on, and there is no operation during this period;

Hi 

Please let me know VIN, VOUT and MOSFET P/N. Also, please share board picture/layout. 

- Eric Lee

hello，

Input voltage is 48V; The output voltage is - 20V; The output current is 3A; The MOS is burnt out in no-load, and CSD19534Q5A and CSD19532Q5B have been used for MOS models respectively; The top and bottom layers of PCB are shown in the figure below：