TPS54202: chip damaged when connect 24V power in

Hi,

Could you please share the layout? If the layout is not good, the spike voltage of VIN and SW would be large, this may lead to the damage.

Shawn

Hi Shawn

Is the layout pic clearly to analyze this problem?

Hi,

The layout is not good, the traces of power stage are too thin, and the trace of SW is under IC, the noise is easy to be introduced to FB, lead to unstable. In addition, input cap is far away from GND pin of IC, the spike voltage of VIN and SW would be very large.Please refer to user's guide to design the layout.

What is the load current? what is the saturation current of the inductor?

Please check if there is the same issue when VIN=12V. And you also can add a 0.1uF ceramic cap close to VIN and GND pin of the IC to double confirm it, this cap can reduce the spike voltage of VIN.

In addition, how did you power the board? Where are the 24V from?

Shawn 

Hi Shawn

Thanks for your advice

The load current is about 100-500 mA, and the  saturation current of the inductor is 2A. The reason I choose this chip is I have it in my hand.

When VIN = 12V, it works.

I have a 0.1uF(C5) at VIN,

I power the board with a 24V adaptor.

Hi,

I know there is 0.1uF cap on the board, but it is far away from the VIN and GND pin of IC, that is why I asked you add another 0.1uF cap close to VIN and GND pin.

Shawn