Index
Introduction
The ESP32 AI Expansion Board is designed to make building a XiaoZhi AI Voice Assistant simple, fast, and reliable. It provides dedicated sockets for the ESP32 WROOM-32 (30-Pin), OLED Display, INMP441 I2S Microphone, and MAX98357A Audio Amplifier, eliminating the need for messy jumper wires.
With its plug-and-play design and convenient USB Type-C power input, you can assemble your AI voice assistant within minutes and spend more time developing intelligent voice applications instead of troubleshooting hardware connections.
Features
Required Components
| Component | Description | Qty |
|---|---|---|
| ESP32 Dev Board | 30 pins | 1 |
| INMP441 I2S Mic | Digital I2S microphone | 1 |
| MAX98357A Amp | I2S audio amplifier | 1 |
| 2W 4Ω Speaker | 2W 4Ω Speaker or any available speaker up to 16Ω. | 1 |
| OLED Display (I2C) 128×64 | Shows pairing code | 1 |
| AI EXPANSION BOARD | For prototyping | 1 |
Circuit Connections
🎤 INMP441 Mic
VDD → 3.3V
GND → GND
L/R → GND
SD → GPIO32
WS → GPIO25
SCK → GPIO26
GND → GND
L/R → GND
SD → GPIO32
WS → GPIO25
SCK → GPIO26
🔊 MAX98357A Amp
VIN → 5V
GND → GND
LRC → GPIO27
DIN → GPIO33
GAIN → GND
BCLK → GPIO14
GND → GND
LRC → GPIO27
DIN → GPIO33
GAIN → GND
BCLK → GPIO14
📺 OLED Display
VCC → 3.3V
GND → GND
SCK → GPIO22
SDA → GPIO21
GND → GND
SCK → GPIO22
SDA → GPIO21
Block Diagram
⚠️ Note: For firmware upload/programming, connect the USB cable to the ESP32 USB port, not the AI Expansion Board USB port.
⚠️ Important: If your AI Expansion Board matches this version, install the microphone in the direction shown. Incorrect orientation may prevent the microphone from working..
Flash Firmware (Browser-Based)
No Arduino IDE required — flash directly from your browser using Web Serial.
- Click “CONNECT” below
- Hold BOOT button on ESP32 and connect USB
- Select the ESP32 port and click Connect
- Choose “Install OceanLabz ESP32” and click Install
- Wait 2 minutes for completion
ESP32 Firmware
Wi-Fi Configuration
After flashing, the ESP32 creates a hotspot named Xiaozhi-XXXX.
- Connect to this Wi-Fi (no password)
- Open
192.168.4.1in browser - Select your home 2.4GHz Wi-Fi and enter password
- Device will restart and connect to your network
⚠️ ESP32 only supports 2.4GHz networks. Use a data-capable USB cable.
Create Account & Pair
1
Reconnect to your home Wi-Fi (exit the XiaoZhi hotspot).
2
Open xiaozhi.me and click on “Console”.
3
Create a free account using Google Sign-Up (fastest method).
Pair Your ESP32
1
Click “+ Add Device” in the console dashboard.
2
Read the 6-digit code scrolling on the OLED display.
3
Enter the code and click Confirm to link your device.
4
Accept the agreement and click “Start Using”, then select Open Source (Free).
⚠️ The code refreshes quickly — enter it as soon as it appears.
Device Paired Successfully!
Your ESP32 is now connected and visible in the console dashboard.
Most Powerful Features & Voice Commands
🔊 Set volume to 50%
☀️ Increase brightness
🌧️ Check weather status
🎵 Play music
😉 Tell me a joke
📊 Get instant AI response
🎤 Press BOOT to activate
Auto-sleep after silence — press BOOT again to wake.
