Hello,
I have a question about TPS23754.
[Problem]
My customer did a wrong design.
He made APD-pin 'floating', though the page-3 of SLVS885H describes as below.
"Tie APD to ARTN when not used."
[Phenomenon]
The current waveform at the time of the start is like an attached file.
An electric current exceeding the specification of PoE+ flows.
Therefore, depending on an opposition device, the system does not start 'Detect and Stopping-output' of PoE repeatedly.
But the system works with no problem after having come by normal start.
[Question]
When the system starts normally, can the system work normally until PoE feeding is interrupted?
(Doesn't the internal FET turn off suddenly?)
In the case of 'Floating', he assumes that the circuit controlling an inrush current does not work correctly.
Therefore, he is thinking that it is no problem in the case that the load does not change like the electric current becoming large suddenly afterwards
if the system stands up even if an inrush current is large.
By the way, he does not require a function guarantee.
Because it is a product which he has already shipped, he wants an opinion as soon as possible.
Regards,
Dice-K
