LM5017: VCC to RTN possible failure mode

Renan Santos Adriano

Part Number: LM5017

Hello Team,

Good day.

MY Customer uses the LM5017MR Synchronous Buck regulator and realized that the VCC supply input is exceeding the absolute maximum rating of 13V. The VCC voltage (supplied by the output of the switching regulator) is dropped by two diodes (Schottky) and the resultant voltage is measured to be 14.4V. I can see on page 5 the spec BST to VCC =100V but I can also see in the same table VCC to RTN = 13V. Do you have any information on the failure mode if this voltage is exceeded?

Thanks in advance.

_Renan

over 4 years ago

0 Harrison Overturf over 4 years ago

TI__Genius 10715 points

Hello Renan,

Let me speak with the engineer responsible for this and I will get back to you with some more information. Please expect 1-2 business day delay in response. Thanks.

Regards,

Harrison Overturf

0 Harrison Overturf over 4 years ago in reply to Harrison Overturf

TI__Genius 10715 points

Hello Renan,

If the customer violates ABSMAX, there is a risk of over-voltage failure within the IC. In this case on the VCC circuitry. The BST to VCC voltage is intended to highlight the 100V diode that exists between those pins. VCC to GND should remain below ABSMAX.

Hope this helps?

Regards,

Harrison Overturf

Power management

Power management forum

LM5017: VCC to RTN possible failure mode