DP83822IF: Behavior at disables 100BASE-FX

Ryo Akashi

Part Number: DP83822IF
Other Parts Discussed in Thread: DP83822I

Hello experts,

I have question about DP83822IF behavior when disable 100BASE-FX.

From datasheet, the difference between DP83822IF and DP83822I is only FX support.

So, if DP83822IF disable FX support function, DP83822IF can be used same as DP83822I?

To do so, we need to set 29pin "OPEN"(datasheet P48). Is my understanding correct?

I would appreciate if you would give me reply.

Thanks and best regards,

Ryo Akashi

+1 Gerome Cacho over 3 years ago

Hello,

Yes, this is correct. If you leave the pin open, it will revert to mode 4 due to the internal pull up, thereby disabling FX support.

Sincerely,

Gerome

0 Ryo Akashi over 3 years ago in reply to Gerome Cacho

Hello Gerome-san,

Thank you for your reply.

I understand DP83822IF can work same as DP83822I when FX support disables.

Let me ask one more question.

If 29pin is High(VDDIO) at start-up timing, does FX support also disable?

Thanks and best regards,

Ryo Akashi

0 Gerome Cacho over 3 years ago in reply to Ryo Akashi

Hello,

If the pin is tied to VDDIO externally, this will also disable FX support, as mode 4 will still be the operating mode for that bootstrap pin.

Sincerely,

Gerome

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