---
title: "W5500 ethernet controller link problem"
url: "https://maker.wiznet.io/Alan/projects/w5500-ethernet-controller-link-problem/"
markdown_url: "https://maker.wiznet.io/Alan/projects/w5500-ethernet-controller-link-problem/md"
type: "UCC: User Created Content"
author: "Thijs"
author_url: "https://electronics.stackexchange.com/questions/607396/w5500-ethernet-controller-link-problem"
editor: "WIZnet"
editor_url: "https://maker.wiznet.io/"
original_author: "Thijs"
original_url: "https://electronics.stackexchange.com/questions/607396/w5500-ethernet-controller-link-problem"
published: "2022-10-24"
language: "en"
likes: 14
views: 931
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# W5500 ethernet controller link problem

> My design includes an STM32, a W5500 and this RJ45 connector which has a 1000pF/2kV capacitor. The problem is that when I connect a cable t

Original author: Thijs (source: https://electronics.stackexchange.com/questions/607396/w5500-ethernet-controller-link-problem)

## Article

Differences that I can see:

1. Ferrite bead between VDD and VDDA

2. Careless impedence matching on RX-TX lines

3. 1Mohm crystal resistor not installed

What is the root cause of this problem and how can I debug it to solve the problem?

---

Source: https://maker.wiznet.io/Alan/projects/w5500-ethernet-controller-link-problem/