---
title: "How to Use ESP32-S3-ETH: Examples, Pinouts, and Specs"
url: "https://maker.wiznet.io/bruno/projects/how-to-use-esp32-s3-eth-examples-pinouts-and-specs/"
markdown_url: "https://maker.wiznet.io/bruno/projects/how-to-use-esp32-s3-eth-examples-pinouts-and-specs/md"
type: "UCC: User Created Content"
author: "cirkitdesigner"
author_url: "https://docs.cirkitdesigner.com/component/ac6eb529-dedf-40f9-b828-e93bf356fe4c/esp32-s3-eth"
editor: "WIZnet"
editor_url: "https://maker.wiznet.io/"
original_author: "cirkitdesigner"
original_url: "https://docs.cirkitdesigner.com/component/ac6eb529-dedf-40f9-b828-e93bf356fe4c/esp32-s3-eth"
published: "2026-04-13"
language: "en"
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views: 915
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# How to Use ESP32-S3-ETH: Examples, Pinouts, and Specs

> The ESP32-S3-ETH is a powerful microcontroller module manufactured by WAVESHARE (Part ID: ESP32-S3-POE-ETH).

Original author: cirkitdesigner (source: https://docs.cirkitdesigner.com/component/ac6eb529-dedf-40f9-b828-e93bf356fe4c/esp32-s3-eth)

## Article

## How to Use ESP32-S3-ETH: Examples, Pinouts, and Specs

![Image of ESP32-S3-ETH](https://abacasstorageaccnt.blob.core.windows.net/cirkit/80103a4f-4892-48b6-b3a9-d5de00ced853.png)

### Introduction

The **ESP32-S3-ETH** is a powerful microcontroller module manufactured by **WAVESHARE** (Part ID: **ESP32-S3-POE-ETH**). It features integrated Wi-Fi and Bluetooth capabilities, along with Ethernet support for reliable wired connectivity. This module is designed for high-performance IoT applications, offering robust communication options and advanced processing power.

### Explore Projects Built with ESP32-S3-ETH

Use Cirkit Designer to design, explore, and prototype these projects online. Some projects support real-time simulation. Click "Open Project" to start designing instantly!

![](https://maker.wiznet.io/upload/ckeditor5/425648727%5F1776067897%2Epng)

#### Common Applications and Use Cases

- **IoT Gateways**: Acts as a central hub for IoT devices, supporting both wired and wireless communication.

- **Industrial Automation**: Provides reliable Ethernet connectivity for industrial control systems.

- **Smart Home Devices**: Enables seamless integration of smart home appliances with cloud services.

- **Data Logging and Monitoring**: Collects and transmits data over Ethernet or Wi-Fi for real-time monitoring.

- **Edge Computing**: Processes data locally with its powerful dual-core processor before sending it to the cloud.

---

### Technical Specifications

#### Key Technical Details

| **Parameter** | **Value** |
| --- | --- |
| **Microcontroller** | ESP32-S3 (Xtensa® 32-bit LX7 dual-core processor) |
| **Clock Speed** | Up to 240 MHz |
| **Flash Memory** | 16 MB |
| **SRAM** | 512 KB |
| **Wireless Connectivity** | Wi-Fi 802.11 b/g/n, Bluetooth 5.0 (LE) |
| **Ethernet Support** | 10/100 Mbps Ethernet with PoE (Power over Ethernet) |
| **Operating Voltage** | 3.3V |
| **GPIO Pins** | 45 (including ADC, DAC, I2C, SPI, UART, PWM, and more) |
| **Power Supply** | PoE or external 5V via USB-C |
| **Operating Temperature** | -40°C to +85°C |
| **Dimensions** | 60 mm x 30 mm |

#### Pin Configuration and Descriptions

| **Pin Name** | **Type** | **Description** |
| --- | --- | --- |
| VIN | Power Input | External 5V power input (used when not powered via PoE). |
| GND | Ground | Ground connection. |
| GPIO0 | Digital I/O | General-purpose I/O pin, often used for boot mode selection. |
| GPIO1-45 | Digital I/O | General-purpose I/O pins with multiple functions (PWM, ADC, etc.). |
| TXD0/RXD0 | UART | UART0 TX and RX pins for serial communication. |
| SCL/SDA | I2C | I2C clock and data lines for communication with peripherals. |
| MISO/MOSI | SPI | SPI data lines for high-speed communication. |
| ETH_TX+/ETH_TX- | Ethernet | Differential pair for Ethernet transmission. |
| ETH_RX+/ETH_RX- | Ethernet | Differential pair for Ethernet reception. |
| RESET | Input | Resets the microcontroller. |

---

### Usage Instructions

#### How to Use the ESP32-S3-ETH in a Circuit

**Powering the Module**:

- Use PoE (Power over Ethernet) for a single-cable solution.

- Alternatively, supply 5V via the VIN pin or USB-C connector.

**Connecting to Ethernet**:

- Connect the Ethernet cable to the RJ45 port for wired communication.

- Ensure the Ethernet network supports 10/100 Mbps speeds.

**Programming the Module**:

- Use the USB-C port to connect the module to a computer.

- Install the ESP32-S3 board package in the Arduino IDE or ESP-IDF.

- Select the correct COM port and board type before uploading code.

**Using GPIO Pins**:

- Configure GPIO pins as input or output in your code.

- Use appropriate pull-up or pull-down resistors if required.

**Wireless Communication**:

- Configure Wi-Fi or Bluetooth settings in your code for wireless connectivity.

- Ensure proper security protocols (e.g., WPA2) are implemented for Wi-Fi.

#### Important Considerations and Best Practices

- **Power Supply**: Ensure the module receives a stable 3.3V or 5V power supply.

- **Ethernet Shielding**: Use shielded Ethernet cables in noisy environments to reduce interference.

- **GPIO Voltage Levels**: Avoid applying voltages higher than 3.3V to GPIO pins to prevent damage.

- **Firmware Updates**: Regularly update the firmware to ensure compatibility and security.

#### Example Code for Arduino UNO Integration

Below is an example of how to use the ESP32-S3-ETH with the Arduino IDE to connect to an Ethernet network and send data to a server:

```cpp
#include <ETH.h> // Include the Ethernet library for ESP32-S3

// Ethernet configuration
#define ETH_CLK_MODE ETH_CLOCK_GPIO17_OUT // Set clock mode
#define ETH_PHY_POWER 12                  // GPIO pin for PHY power

// Network credentials
const char* server = "example.com";       // Server address
const int port = 80;                      // Server port

void setup() {
  Serial.begin(115200);                   // Initialize serial communication
  ETH.begin(ETH_PHY_POWER, ETH_CLK_MODE); // Initialize Ethernet

  // Wait for Ethernet connection
  while (!ETH.linkUp()) {
    Serial.println("Connecting to Ethernet...");
    delay(1000);
  }
  Serial.println("Ethernet connected!");
}

void loop() {
  // Example: Send a GET request to the server
  WiFiClient client;
  if (client.connect(server, port)) {
    client.println("GET / HTTP/1.1");
    client.println("Host: example.com");
    client.println("Connection: close");
    client.println();
    Serial.println("Request sent!");
  } else {
    Serial.println("Connection failed!");
  }
  delay(10000); // Wait 10 seconds before sending the next request
}
```

---

### Troubleshooting and FAQs

#### Common Issues and Solutions

**Ethernet Not Connecting**:

- Ensure the Ethernet cable is securely connected to the RJ45 port.

- Verify that the network supports 10/100 Mbps speeds.

- Check if the PoE switch or injector is functioning correctly.

**Wi-Fi Not Connecting**:

- Double-check the SSID and password in your code.

- Ensure the Wi-Fi network is within range and not overloaded.

**Module Not Detected by Computer**:

- Verify the USB-C cable is functional and supports data transfer.

- Install the correct USB drivers for the ESP32-S3.

**GPIO Pins Not Working**:

- Confirm the pin mode (input/output) is correctly set in the code.

- Check for short circuits or incorrect wiring.

#### FAQs

**Q: Can I use both Ethernet and Wi-Fi simultaneously?**
A: Yes, the ESP32-S3-ETH supports simultaneous Ethernet and Wi-Fi operation.

**Q: How do I update the firmware?**
A: Use the ESP-IDF or Arduino IDE to upload the latest firmware via the USB-C port.

**Q: What is the maximum Ethernet cable length?**
A: The maximum recommended length is 100 meters (328 feet) for standard Ethernet cables.

**Q: Can I power the module with a battery?**
A: Yes, you can use a 3.7V LiPo battery with a suitable voltage regulator to provide 3.3V.

---

Source: https://maker.wiznet.io/bruno/projects/how-to-use-esp32-s3-eth-examples-pinouts-and-specs/