TPS62933P: Pin FMEA results

keita.shoji

Part Number: TPS62933P
Other Parts Discussed in Thread: TPS62933

Hi,

During the product development, we found a condition where a short circuit of two adjacent pin results in potential fire.

When connection between BST and PG is shorted, the device started drawing more current and burned an area around VIN pin. Eventually connection at VIN pin broke off and fire is extinguished by itself.

We would like to ask you two questions:

1. Do you have pin FMEA results for this part?

2. Do you know how to mitigate potential hazards during adjacent pin fault like this.

Best regards,

5 months ago

0 Miranda Gu 5 months ago

TI__Genius 15047 points

Hi Keita,

1. We have TPS62933 pin open short test results, as shown below.

In our test, we set 1A OC limit for input supply, so we didn't see a severe damage like yours.

2. PG-pin is low-voltage pin while BST-pin is high-voltage pin. During device operation, BST voltage will be about 3V~5V higher than SW voltage, so PG-pin cannot be connected to BST-pin directly.