LM5017: IC burning up

Hi 

Do you mean frequently disconnect the Vin from the Battery or disconnect the Vout with the load(MCU) ?

Why is the RR,CR,CAC disconnected?

Thanks

I beleive they are used to smoothen the ripple right?, So just to check basic function i omitted them

Hi Mounish

The ripple injection network is needed to stabilize the circuit, otherwise the Cout should have some ESR to realize the vout feedback.

Can you reproduce the failure by frequently power on/off the Vin?

Yes ,that is the issue actually,

I was able to reproduce the failure. So,e times failure happens after 3 times, some times 15 times but it is happening, I would like to know why this is happening?

and every time i see failure, I see failure from second pin of IC. How to solve this?

Thanks & Regards

Mounish 

Hi Mounish

Is Vin a stable voltage? Can you capture the waveform of Vin when power up/off?

Thanks

VIN is from the Battery, IC is burning up only during transition state ( lets say 1 of 15 Cases ), but once it is connected everything safe. I personally feel the inrush current or surge is frying IC. How to fix it?

Hi Mounish

Can you place the RR,CR and CAC as specified in the schematic on the PCB, and see if this can help?

Thank you

Hi Mounish

I checked with other experts. Seems like this is related to the Cin,  can you please try adding the Cin and see if this can help?

Thanks and best regards.