TPS782: Damaged Component/ Wrong Output After Reflow Soldering

user4863328

Part Number: TPS782

Hello,

We are using TPS68233 on our board. After we receive boards from automated reflow soldering process, we notice that more than half of TPS68233's provide wrong output voltage, most of them at 1.6v OR 1.7v. When we desolder and replace newer one by soldering manually, we get correct output, 3v3.

We checked device marking as well, "OAH", which is correct. What is the problem here? Should we check reflow temperatures or do you have any other solution?

Thank you.

over 8 years ago

0 Kyle Van Renterghem over 8 years ago

TI__Genius 14245 points

Hi,

You mention that you replaced the failing devices with new ones and soldered them by hand. Did you attempt to resolder any of the failing devices by hand? If the automated soldering process didn't do a good job of connecting the IN and/or OUT pins to the PCB then the high resistance may cause the output to show a lower than expected voltage (assuming there was some load current).

-Kyle

0 user4863328 over 8 years ago in reply to Kyle Van Renterghem

Prodigy 20 points

Yes, we are sure that components are damaged. We resoldered these to make sure connections are good, but result is the same.

0 Kyle Van Renterghem over 8 years ago in reply to user4863328

TI__Genius 14245 points

ok, that makes me think that the devices may have been damaged during or after the board assembly process. It seems like the pass device has been electrically overstressed, is it possible that the ESD ratings or Abs Max ratings could have been exceed somehow?

-Kyle

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TPS782: Damaged Component/ Wrong Output After Reflow Soldering