LMR50410-Q1: IC getting burned/ short issue

Hi Ankush

"U2 IC which converts 5VD to 3.3VD got burned near pin5 (Vin) and pin 4 (EN)  immediately after power up."--What's the load now? Also, what happened after the device fail, did the VIN-SW or SW-GND short?

Thanks and best regards.

Hi Gui he,

You can consider R9 and R10 resistor divider network and  R11 and R12 resistor divider network as the only load connected to 3.3V output

Sample 1:  PIN 6 (SW) and PIN 1 (CB) are short internally  (burn mark near pin 4 and 5)

Sample 2:  None of the PINs are short internally   (burn mark near pin4 and 5)

Sample 3:  PIN 5 (VIN) and PIN 2 (GND) are short internally (no visible burn marks on the surface of IC)

Thanks.

HI Ankus

Please let me take a look and reply to you later.

Thanks and best regards.

Hi Ankus

Can you remove the L10,L11 and see if it can operate well ? You can also try  replacing the L9 as 2uH 

Thanks and best regards.

Hi Gui He,

I swapped the damaged ics with fresh ones and there is no issue till now.

I will do the the changes given by you and test it and get back to you.

Thanks.

Hi Ankush

Thank you for the updates. And sorry for late reply.

Thanks and best regards.