TPS65217: nINT signal remains low on power up

Daniel Brown

Part Number: TPS65217

My PMIC nINT signal is low, however. I am using the TPS65217C. I don't know why this signal is low on power up. I have modified my board to pull it up to 3.3V instead of 1.8V. This signal is connected to NNMI on the AM3358. I Schematic is attached. Can somebody please help.106515-PCB_TORSO_BASE.PDF

over 8 years ago

0 Kevin LaRosa over 8 years ago

TI__Genius 17380 points

Hi Daniel,

Are you clearing the interrupts? What do you see in the interrupt register (section 9.6.4 of the datasheet)? This signal is active low, so if there are interrupts pending then it will stay low, regardless of what you pull it up to.

0 Daniel Brown over 8 years ago in reply to Kevin LaRosa

Intellectual 870 points

We do have have u-boot and QNX up and running but do not yet have software to a point where we can check that register. That is on my list to do. That said, I would have thought that the initial power-up state of the nINT signal would be high given that there do not seem to be any of the obvious interrupt events occurring.

0 Kevin LaRosa over 8 years ago in reply to Daniel Brown

TI__Genius 17380 points

Hi Daniel,

The interrupts (Push button, AC, and USB) correspond with the turn on sources (pg. 19 of datasheet), so I would expect nINT to always be asserted low on start-up. Processor can then go in to identify what caused the turn on and clear the interrupt. After it is cleared, it should re-assert if any of those three change again. Hopefully once you get the next layer of software up, you should be able to clear the interrupts and see nINT go high.

0 Daniel Brown over 8 years ago in reply to Kevin LaRosa

Intellectual 870 points

Okay. Thanks.

Power management

Power management forum

TPS65217: nINT signal remains low on power up