LMR36503-Q1: Questions on LMR36503 FMEA

Christina Lim

Part Number: LMR36503-Q1

Hi,

My customer had some questions on TI's LMR3650x functional safety Pin FMA documentation as well as pin to pin failures that are not listed in our document.

We would like to try and better understand some of the outcomes regarding the pin to pin failures, and open-circuit pin failures in the document. For a number of scenarios that we are concerned about (listed in the below table that failure leads to ‘potential device damage.’ Please could you provide some further analysis as to what this may look like? For example, large leakage currents into a pin, or overheating of the IC/external circuitry.

There are also a number of further pin to pin failures that are not listed in your document, as they are not adjacent pins. Would it be possible to provide an assessment of the outcome of these failures?

Thanks,

Christina

7 months ago

0 Elena Gao 7 months ago

TI__Genius 13735 points

hi, Christina,

All the PIN FMEA report list in the table, please see below, and which is not include, please list you concern ,I can help.

https://www.ti.com/lit/fs/snvaa01/snvaa01.pdf?ts=1701320275174&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FLMR36503-Q1%253FkeyMatch%253D%2526tisearch%253Dsearch-everything%2526usecase%253Dpartmatches

Elena

0 Christina Lim 7 months ago in reply to Elena Gao

TI__Expert 5465 points

Hi Elena,

Customer already reviewed the document, they need more clarity on :

For a number of scenarios that we are concerned about (listed in the below table that failure leads to ‘potential device damage.’ Please could you provide some further analysis as to what this may look like? For example, large leakage currents into a pin, or overheating of the IC/external circuitry.

Also the list they are concerned about is the table above.

Thanks,

Christina

0 Elena Gao 7 months ago in reply to Christina Lim

TI__Genius 13735 points

hi, Christina,

Open VCC pin will damage because VCC is for internal logic power voltage .open BOOT will not able open HS so device will not work , no output . as below.

Most pin short to VIn will lead to damage because of the pin max voltage .

Damage is easy to found ,like the internal diode is damage, you can test the diode from Vin-SW, SW to GND.

Other B grade issue will effect the function ,you can test the Vout is not operating ,or unstable, even no output.

Elena

Power management

Power management forum

LMR36503-Q1: Questions on LMR36503 FMEA