---
title: "W5500 no 1.2v"
url: "https://maker.wiznet.io/forum/9890"
markdown_url: "https://maker.wiznet.io/forum/9890/md"
type: "Forum topic"
category: "Ethernet Chips"
author: "mickle"
created: "2014-02-04T01:54:30+09:00"
last_activity: "2017-05-04T08:31:12+09:00"
language: "en"
views: 449
replies: 1
source: "WIZnet Makers forum (https://maker.wiznet.io/forum/)"
---

# W5500 no 1.2v

## Question

Asked by mickle on 2014-02-04 in Ethernet Chips.

I’ve just built a new PCB with the W5500, and it does not respond to any SPI commands.

I have verified all the ground and 3.3v pins are connected to power supply.

I measure zero volts on pins 1V20, TOCAP and VBG.

Is there something that needs to be done to enable the internal 1.2v regulator, or some reason it isn’t functioning?

thanks.

## Replies

### Reply 1 by mickle, 2014-02-04

OK, problem solved. It was in fact a bad solder joint on pin 21, AVDD, right next to the 1V20 pin.

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Source: https://maker.wiznet.io/forum/9890