Wiznet w5500 schematic layout verification

TCP/IP Chip W5500
1

Hello ,
We are designing our custom PCB using W5500 's reference design. We wanted to make sure that it is thoroughly verified by Wiznet technical experts before going for mass manufacturing.
Please find the attached schematic and layout and suggest any changes or improvements are needed?

Thanks ,
Omkar

wiznet schematic
wiznet schematic1160×693 148 KB

wiznet layout
wiznet layout461×620 103 KB

2

The circuit looks fine. However, when designing a PCB, the Ethernet line should be designed as a differential pair. It is recommended that the impedance be adjusted to 100 ohms.

3

Hi Alan,
Thank you for your response. We are facing one more issue while using wiznet w5500. We have observed that whenever inductive load such as contactors are triggered near w5500 circuit,
it resets. We had put the query before on this link : W5500 False Reset due to AC switching noise - #6 by ayushjain1912 . Please let me know if you may add anything more.

Regards,
Omkar

4

Is “Reset Line” the W5500’s “Reset Line”?
Every time the inductive load you mentioned is loaded, the surge power splashes too hard… It doesn’t look normal. I think we need to turn it on properly first. Isn’t the GND line firm?

I replied to you via link.

5

Hello Alan,
Thank you for your response. Yes, the reset line is W5500 reset line. By “turn it on properly first”, do you mean W5500 or the inductive load in this scenario? We have the GND plane on the entire PCB.

6

image
image1035×466 64.2 KB

It meant that we need to get all the VCCs right first. It is strange that the VCC bounces like the image above depending on the induced load. It’s sticking out too much.

7

Hello Alan,
In our system, input supply is clean. There is no VCC bouncing as shown in your image. We have microcontroller which works fine, only w5500 resets in above case.

8

Is that so? Can you tell me a more accurate situation? I don’t think I know the exact situation.

9

If you send me the whole circuit diagram, it will be easy for me to figure it out.