TPS65094: TPS65940A0 Usage defect

lixiangyang

Part Number: TPS65094

Tool/software:

Hello:

I used your TPS650940A0RSK for Intel Apollo Lake design. We produced 10 boards, and one of the boards had a power failure in the system. It appears to be a power drop on the 1.8V output (BUCK4) causing the PMIC to have no output.

Problems with the welding or the chip itself can be ruled out for now. Because it is good at the beginning, it can work normally, and this problem occurs after a period of aging. The maximum temperature of the IC was 45.1℃ at normal temperature 25℃ and 68.4℃ at 60℃. The chip has problems when used at room temperature, which should have nothing to do with temperature. I would like to analyze what causes it. Could you please give me some ideas on how to solve the problem?

9 months ago

0 Matt Sunna 9 months ago

TI__Guru* 80964 points

Hi,

Are you able to remove the chip to perform an ABA swap? This will help isolate whether the failing behavior follows the unit and that the board performs well with a different unit.

Best regards,

Matt

0 lixiangyang 9 months ago in reply to Matt Sunna

Prodigy 10 points

Hello:

Did a cross test, found that the problem followed the chip, but it was good at the beginning, and the problem was found in the process of use. At present, I have ruled out the possibility of temperature burning the chip, the current is not used in overload, the schematic design is consistent with the demo board, may I ask what other possible reasons?

0 Matt Sunna 9 months ago in reply to lixiangyang

TI__Guru* 80964 points

Typically damage to the device requires violation of the Absolute maximum parameters (over-voltage, over-current, temperature extreme) conditions listed in the datasheet. If you can identify which pins show signs of damage, then it may be good to monitor these pins with an oscilloscope in the system on a working board to see if there are any unexpected voltage transients.

0 lixiangyang 9 months ago in reply to Matt Sunna

Prodigy 10 points

When measuring each pin of the chip, no obvious abnormality was found. When measuring the waveform, BUCK3,BUAK4 and BUCK5 all showed voltage drop. According to the waveform, BUCK4 fell first, recovered after falling, and then all the electricity failed together.