LM63625QDRREVM: LM63625DQDRRRQ1

Hi Aden

Can you please help clarify what kind of failure it is? And under what operate condition, What's the VIN and the load? 

Thank you

Hi 

Is the issue still there? I am going to close the thread for now due to inactivity, you are free to reopen or start a new thread.

Thank you.

HI Gui,

I sent a reply but it keeps getting kicked back. Hopefully this one will go through.

VIN = 24V

Iload = 700mA

See below picture where the damage is visible in the chip.

Hi Aden

Currently the issue I saw is that:

For Vin=24V Vo=1.5V, the D is small, =0.063 (even smaller when Vin=30V). The ton=D*Ts, which is very small considering the fsw is very high. For 24V->5V, 2.1MHz, the ton is around 30ns. Which is larger than the ton_min specified in the datasheet (Table 7.6).

The HS will keep conduction during the ton_min time.

Can the fsw be changed? Can 400kHz be used here? But you will need to select a larger Lm inductor if use 400kHz , I think ~4.7uH will be ok.

Thank you.

Hi Gui,

Thank you for the suggestion. I will evaluate using the 400Khz fsw.