Offline wake word
The VB6824 offline voice engine detects the wake word on-device; audio is only streamed when the device is addressed.
Smart Home & AI / Solution
Voice Wake Module + LLM Interface
Offline voice wake, dual-band Wi-Fi 6 / 4G and a round display for AI toys, companion robots and smart-home devices.
Start a brief
01Overview
A reference module for AI toys and companion devices: wake word on-device, then a cloud or local LLM for conversation, expressions and device actions.
The ULINK-M33 kit contains six parts: ESP32-C5 core board, 2.0-inch round display, 4G Cat.1 module, microphone, 1200 mAh battery and 8 Ω 1 W speaker. It supports offline voice wake (VB6824), dual-band Wi-Fi 6, BLE 5.4 and 4G Cat.1.
The module can access 小智 AI and cloud LLM providers such as Doubao, DeepSeek, ChatGPT and Qianwen, with changeable roles and an expression UI. GPIO, audio and Type-C interfaces support sensors, extra displays and OTA updates; the same architecture can be adapted to smart-home devices.
02Key features
What the product actually changes.
Each feature should map to a specification, a test or a documented application — not a generic marketing claim.
Wi-Fi 6 + 4G Cat.1
ESP32-C5 provides dual-band Wi-Fi 802.11b/g/n/ax and BLE 5.4; the NT26 module adds LTE Cat.1 for mobile use.
2.0-inch round display
A 240 × 296 round display for eyes, expressions, status and a simple UI without a phone.
LLM access
Works with 小智 AI and cloud providers including Doubao, DeepSeek, ChatGPT and Qianwen, with changeable character roles.
Six-part modular kit
Core board, display, 4G module, microphone, 1200 mAh battery and 8 Ω 1 W speaker can be assembled and serviced separately.
Expansion and OTA
GPIO, audio and Type-C interfaces support sensors, extra displays, programming and firmware updates.
03Working principle
How it works, stage by stage.
The microphone captures speech, the VB6824 engine detects the wake word, and the ESP32-C5 streams audio through Wi-Fi or 4G to the selected LLM; the reply drives speech and the round display.
- 01
Wake
The offline engine detects the wake word and starts the interaction without sending continuous audio.
- 02
Connect
ESP32-C5 uses dual-band Wi-Fi 6 or the 4G Cat.1 module to reach the cloud service.
- 03
Reason
ASR, LLM and TTS run in the cloud (or on a local host); the module receives text/audio and an emotion state.
- 04
React
The 8 Ω 1 W speaker plays the reply and the round display shows expressions; GPIO can drive motion or lights.
04Model selection
Specifications and model selection.
Compare the series against the requirement. Every value should state its unit and test condition.
Reference ULINK-M33 configuration from the supplied product sheet. Other controllers, display sizes and radios are available per project.
| Model | Controller | Wireless | Display | Audio | Battery |
|---|---|---|---|---|---|
| ULINK-M33 | ESP32-C5 | Wi-Fi 6 2.4/5 GHz + BLE 5.4 + 4G Cat.1 | 2.0 in / 240 × 296 | Mic -32 ± 3 dB, 8 Ω 1 W | 1200 mAh |
| Custom | ESP32 / Linux-class | Wi-Fi / BLE / 4G | 2.0–2.8 in | Custom | 1200–3000 mAh |
- ULINK-M33 module dimensions: 65 × 30 mm; IP44; operating temperature -20 to 80 °C.
- 128 Mbit flash; Type-C for power and programming; Boot and pairing buttons; RGB and battery-status LEDs.
- 4G module: NT26, based on the EC716 / EC718 LTE Cat.1 bis platform.
- Radio certification depends on the final module, antenna and enclosure.
05Applications
Where it fits.
Add the operating requirement that makes this product a good match — not just an industry logo.
AI plush toys
Round display, voice wake and LLM conversation for plush toys and companion robots.
Smart speakers & hubs
Add wake-word and conversational control to a speaker, display or home hub.
Appliances
Voice control for kitchen, laundry, lighting and HVAC products without a full screen.
Hotel & elder care
Room control and assistance requests with privacy modes and local fallback.
06Custom development
Custom PCBA, firmware and app development
The ULINK-M33 is a reference kit. The same architecture can be developed around your product: a custom board, firmware, mobile app and cloud service, with certification support.
- 01Hardware and PCBA design, including radio and antenna integration
- 02Firmware, offline wake word, audio front end and OTA updates
- 03Mobile app and cloud API for setup, content, diagnostics and device management
- 04EMC / CE / UL certification support and production test fixtures
07Compliance & quality
Claims backed by documents.
Certificate scope and test reports are supplied on request. “Project-specific” means the standard is confirmed for the selected configuration; “pending” means it has not yet been verified for publication.
- CE / FCC / RoHSProject-specific
Design and documentation support; final scope depends on the selected radio module and enclosure.
- Privacy by designProject-specific
Wake-only capture, hardware mute and local-only options are part of the module specification.
08Downloads
Take the documents with you.
Datasheets and drawings can be shared directly with your engineering and procurement teams.
09Related solutions
Next step
Need stock or a custom version?
Send the application, target volume and market for Voice Wake Module + LLM Interface. We will confirm stock availability or scope a custom build, with samples and a production plan.