WT99C202-AI-S2 Feature Introduction

1. Introduction

The WT99C202-AI-S2 development board is a multimedia development board launched by Shenzhen Wireless-tag Co., Ltd., based on the WT01C202-AI-S1 module. The WT01C202-AI-S1 module is an intelligent voice AI module designed based on Espressif's ESP32-C2 series chip, supporting 2.4 GHz Wi-Fi, Bluetooth LE v5.0, and local voice control. Additionally, the WT99C202-AI-S2 supports offline/online voice conversation and OTA upgrades, and can be connected to various AI large models such as ChatGPT, Dify, Coze, etc., meeting customers' development needs for rapid integration of AI intelligent products.
This development board integrates microphone, speaker modules, and supporting applications, supporting plug-and-play functionality. Customers can directly integrate it into existing product systems, significantly shortening the development cycle.

1.1 🔧 Core Hardware Configuration

• Main Control Chip: Equipped with Espressif's latest ESP32‑C2 chip, integrating 2.4 GHz Wi‑Fi (supporting IEEE 802.11 b/g/n) and Bluetooth 5 LE. It adopts a 120 MHz RISC‑V single-core processor architecture, with built-in 272 KB SRAM (16 KB for cache) and 576 KB ROM. While superior to ESP8266 in both size and cost, it provides excellent RF performance, high integration, and ultra-low power consumption.
• Speaker + Microphone: Uses FM8002A power amplifier, capable of driving 1.5W to 8Ω load or 2W to 4Ω load. Driven via ADC and PWM.

  ! ⚠️ Note: ESP32C2 does not support I2S.

• Lithium Battery Charge/Discharge: Supports lithium battery charging and discharging, allowing operation without power cables. Compact and portable.

1.2 🛠️ Design Features

1. Compact and Portable AI Development Board: Supports lithium battery charging and discharging, with overall dimensions of only 36 x 48 mm.
2. Pins are brought out via connectors, facilitating secondary development.
3. Designed using the WT01C202-AI-S1 module, with simple power supply circuit and high cost-effectiveness.

1.3 ⚙️ Development Advantages

• Open-source software examples facilitate user modification and secondary development.
• Supports xiaozhi and Guisi Wuyu platforms, making it convenient for users to connect with major AI platforms.
• Voice independent chip control, supporting custom wake words.

2. Pin Description

3. Power Characteristics

You can choose one of the following power supply methods for the WT99C262-SG series development board:

• External power supply via USB Type-C interface;
• Use the 3V3 power input port and connect corresponding voltage via Dupont wires;
• Power via the power connector using a lithium battery;