---
title: "[From QnA] WIZ220IO Pin Definitions"
url: "https://maker.wiznet.io/forum/9602"
markdown_url: "https://maker.wiznet.io/forum/9602/md"
type: "Forum topic"
category: "General"
author: "irina"
created: "2013-10-02T07:45:02+09:00"
last_activity: "2020-12-14T04:26:19+09:00"
language: "en"
views: 761
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# [From QnA] WIZ220IO Pin Definitions

## Question

Asked by irina on 2013-10-02 in General.

## This post came from QnA of WIZnet website

I’m embedding a WIZ220 module into another product, and have a few questions:

1. Can these boards be modified to run on 3.3V instead of 5V (i.e. bypass the on-board LDO)?

2. I see some products have a version without an RJ45 and magnetics. I would prefer to AC couple the PHY output directly into an unmanaged Ethernet switch, and avoid the magnetics. Is there a version of the 220 with direct PHY output? If not, can the 220 be ordered with the RJ45 unpopulated?

3. What is the purpose of the F_RST pin? Under what conditions would we need the ability to pull this pin low?

4. I see no definition for the P2_2 or P2_4 pins. They’re unconnected on your base board. What are they?

Thanks,
Gary

## Replies

### Reply 1 by irina, 2013-10-02

Dear customer,

Thanks for your interest in WIZ220IO.
I answer you about your question.
You can use power 3.3V instead of 5V. However, it is necessary to supply a stable voltage for the 3.3V, when the unstable power is supplied to the chip , it may break the chip.
There is no version that can be used without RJ45.
F_RST pin is used to the Factory reset.
I used directly to pin that is not currently in use.

Thanks,
WIZnet

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Source: https://maker.wiznet.io/forum/9602