LMR33630: Please help to check the design if something wrong, chip burned once added a 24V DC input

Yue TANG

Part Number: LMR33630

Hi Team,

Please help to check below deisgn. my customer is the first time to use LMR33630ADDA, 24V input and 5V output. When they added 24V supply, the chip burned.

over 5 years ago

0 Marshall_Beck over 5 years ago

TI__Mastermind 28980 points

Hi,

Is this part failure reproducible, under the same conditions?
Could you please have the customer check the FB path and VCC net to see if everything is wired up correctly and agrees with the schematic?

Thanks!

0 Frank De Stasi over 5 years ago in reply to Marshall_Beck

TI__Guru 57555 points

It does not look like you have the required input capacitor.
Please consult the data sheet for the proper component values.
Also, be sure that the DAP is soldered to a good ground plane for
power dissipation.

0 Yue TANG over 5 years ago in reply to Frank De Stasi

TI__Expert 8485 points

Thanks for the suggestion. I had them check the PCB connectivity, it match their schematic. so far, their this batch PCBA all has the same issue. also ,they soldered the bottom PAD to the ground and change the input capacitor to 10uf electrolytic capacitor and 220nf MLCC, but still not resolve. their design do have some thermal dissipation problem, but they didn't add any load. Do you have more suggestion about this issue?

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LMR33630: Please help to check the design if something wrong, chip burned once added a 24V DC input