---
title: "Error in Wiznet 5500 Schematic?"
url: "https://maker.wiznet.io/forum/16099"
markdown_url: "https://maker.wiznet.io/forum/16099/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "mike215611"
created: "2026-06-23T04:22:24+09:00"
last_activity: "2026-06-26T11:33:09+09:00"
language: "en"
tags: ["W5500"]
views: 4
replies: 3
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Error in Wiznet 5500 Schematic?

## Question

Asked by mike215611 on 2026-06-23 in Ethernet Chips.

I note the Receive center tap pin on your Wiznet W5500-Pico-POE reference is tied to +3.3V. On wiz850io_sch_v100.schdoc reference designes it is tied to ground via a .1uf cap. Does it matter?

I am working on building a custom board with the W5500 using a TRJ4284AHNL magjack with POE.

## Replies

### Reply 1 by Alan, 2026-06-23

I am sorry, but I do not fully understand what you mean.
Please send the detailed explanation by email.

Alan@wiznet.io

### Reply 2 by mike215611, 2026-06-24 (in reply to reply 1)

i Allan,

See the two attached schematics I obtained from Wiznet. There is a conflict on how the receive center tap is connected for interface with your W5500.

On W5500-EVB-Pico-POE look at P4 pin 5 (RCT). It is directly connected to 3.3V.

On wiz850io_sch_v100 , P1 pin R4 (RCT) it is connected to AGND through a 10nf cap.

Which one is correct? I need your best reference and recommendation to connect W5500 to a magjack with POE support. I am looking at using the TRXCOM TRJ4284AHNL for the magjack.

Many thanks,

Michael

![image.png](https://mail.google.com/mail/u/0?ui=2&ik=2a8c89baf4&attid=0.0.1&permmsgid=msg-a:r-1093566261415224523&th=19ef465dfdcf8689&view=fimg&fur=ip&permmsgid=msg-a:r-1093566261415224523&sz=s0-l75-ft&attbid=ANGjdJ8NKXJBeTgLj5MY8_2seU87W5opTaMnf7KDAcigE_7FOpp5svHrf76KTgiUpVOSLvEVeTK0XwPJvFPYO81lF300x2030ynwFYx_Ce4VvXigqwG7ySStu0jK60k&disp=emb&realattid=ii_mqqltefj3&zw)

![image.png](https://mail.google.com/mail/u/0?ui=2&ik=2a8c89baf4&attid=0.0.2&permmsgid=msg-a:r-1093566261415224523&th=19ef465dfdcf8689&view=fimg&fur=ip&permmsgid=msg-a:r-1093566261415224523&sz=s0-l75-ft&attbid=ANGjdJ_YkCyntmhmFf9rii-H3t0mPLADg2sP5ofr_iC40wd7CwZvSrum7qp5G91Crp279Cz51pcmtRhWaZTvjLfnJFePCckWg5bwmlswkAqAGV2ziexh5axB16RHMKc&disp=emb&realattid=ii_mqqlu0ph4&zw)

### Reply 3 by mike215611, 2026-06-26 (in reply to reply 1)

Anyone at Wiznet comment on the above schematic and possible error?

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Source: https://maker.wiznet.io/forum/16099