W5500 RSVD pins - connect to GND or leave floating?

TCP/IP Chip W5500
1

Hi. I saw that there is difference between application note and datasheet of W5500.
What should I do with RSVD pins?

There is schematic where each RSVD pin is floating (application note)

In datasheet there is information that
23 RSVD Pull-down I It must be tied to GND and Rest sould be floating.

There is W5500 devboard where each RSVD is connected to GND via 10k resistor.

What should I do?

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2

These pins are already having internal pull-downs averaging at 85k. Thus the question is are these internal pull-downs enough and why some circuits have external pull-downs, and some not?

3

Yes, i saw that here are pulldowns at RSVD pins.
So when RSVD should have external pull down?

4

No idea. We must wait for WIZnet R&D to advise. If you need to make a design right now, just leave seats for those resistors, and will decide if to populate them or not later.

5

Thanks Eugeny. So we will wait :slight_smile:

6

Hi kewgal

As Eugeny said, W5500 RSVD pin has internal pull-down(thanks Eugeny!).

The internal pull-down resistance value of 85K is too large and can be swayed by external noise. That’s why we used an external pull-down resistance of about 10K.

Reset pin is internal pull-up but as the same reason with RVSD pin, it can be use with external pull-up.

Thanks!

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