TPS82084 PG pin got 20mA sink current during 2ms

Thomas Chang15933

Expert 4770 points

Other Parts Discussed in Thread: TPS82084, TUSB7320

Dear Team:

Our customer used TPS82840, and PG pin got 20mA sink current during 2ms.

Does it damage the chip?

Could you analyzer the condition?

over 7 years ago

0 Chris Glaser over 7 years ago

TI__Guru*** 142710 points

Please fix the typo in the part number. TPS82840 does not exist.

The schematic is a little blurry. Do you have a better one?

What does the waveform show?

0 Thomas Chang15933 over 7 years ago

TI__Expert 4770 points

Sorry about My trpo.
The correct P/N is TPS82084.

0 Chris Glaser over 7 years ago in reply to Thomas Chang15933

TI__Guru*** 142710 points

Thanks for clarifying the part number. Please edit the title of your post and reply to my other questions.

Yes, 20 mA is well-beyond the 1 mA abs max rating, so this cannot be recommended. Since the PG pin is an open drain output, you must limit the current into it. Typically, this means increasing the pull-up resistor value.

0 Thomas Chang15933 over 7 years ago in reply to Chris Glaser

TI__Expert 4770 points

Dear Chris:
OK, we know the limitation by datasheet.
But I think 1mA sink current is for continue operated, if it only 3mA sink current during 2ms , whether it damage the chip?
Because right now it is work around solution for TUSB7320 FA issue, that PG pin glitch is around 3 mA during 2ms.
So, could you help us to analyze this condition?

0 Chris Glaser over 7 years ago in reply to Thomas Chang15933

TI__Guru*** 142710 points

The abs max limits are for DC signals. 2 msec is DC. It's still not clear why you have this condition in your system. Can you share the proprietary details via email?

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TPS82084 PG pin got 20mA sink current during 2ms