---
title: "Wiznet550se2 TX and RX route Impedance"
url: "https://maker.wiznet.io/forum/12353"
markdown_url: "https://maker.wiznet.io/forum/12353/md"
type: "Forum topic"
category: "Serial-to-Ethernet & ConfigTool"
author: "nurettintn"
created: "2017-06-30T14:33:49+09:00"
last_activity: "2017-07-03T05:37:41+09:00"
language: "en"
views: 1055
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# Wiznet550se2 TX and RX route Impedance

## Question

Asked by nurettintn on 2017-06-30 in Serial-to-Ethernet & ConfigTool.

Hello,

I can’t find any impedance information for nodes; TX_N, TX_P, TX1_P, TX1_N and RX_N, RX_P, RX1_P, RX1_N in wiznet550se2 reference schematic design. [wiz550s2e reference schematic](http://wizwiki.net/wiki/lib/exe/fetch.php?media=products:wiz550s2e:schematic1_wiz550s2e_v1.pdf)

Could you please provide me a proper impedance spec for these tracks if there is one?

Thank you in advance,

Nurettin

## Replies

### Reply 1 by Edward, 2017-07-03

Hi

What impedance information do you want?

The line must consist of 50R lines.
And because it is a differencial signal, the trace must match.
The circuit diagram includes an impedance matching circuit. (Circuit below)

[![](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/5/5616b6c4d1ae0c50a4a82cc9d70dc256f4ffecca.png) 1010×513 34.7 KB](https://maker.wiznet.io/forum_uploads/wiznet/original/2X/5/5616b6c4d1ae0c50a4a82cc9d70dc256f4ffecca.png)

Let the trace between W5500 and magnetic as short as possible, and keep the TX +/- (same as RX +/-) signal traces to be symmetry. The traces should not be too long and 12cm will be the maximum length of the path.

Thank you.

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Source: https://maker.wiznet.io/forum/12353