M5Stack Atomic Voice Base with Microphone and Speaker is a compact voice recognition base designed for the M5 Atom series. This Atomic Voice Base adds a complete audio input and output path to a compatible Atom host, combining the ES8311 mono audio codec, a MEMS microphone, and the NS4150B Class-D amplifier with a built-in 1W 8Ω speaker. Unlike an integrated Atom Echo style controller, this product is a base module without its own main SoC. It is built for projects that need full-duplex audio, I2S voice interaction, voice wake-up, speech playback, and compact smart home voice control. It is especially useful when paired with an AtomS3R host for Home Assistant, OpenAI voice assistant, and other embedded voice assistant workflows. Features Built for the M5 Atom series, adding microphone and speaker capability through the Atom base interface. ES8311 mono audio codec with 24-bit resolution and 16KHz to 64KHz sampling support. MEMS microphone optimized for voice recognition and embedded audio input. NS4150B Class-D amplifier driving a built-in 1W @ 8Ω speaker. Full-duplex audio communication for simultaneous input and output. I2S-based audio path suitable for wake word, voice interaction, and playback workflows. Compact 24 × 24 mm footprint that matches the Atom family form factor. Official support materials for Arduino, UiFlow2, and ESP-IDF based development. Specifications Specification Parameter Product Type Atomic Voice Base for M5 Atom series Audio Codec ES8311, 24-bit resolution, I2S protocol MEMS Microphone MSM381A3729H9BPC, SNR ≥ 65 dB Power Amplifier NS4150B Class-D amplifier Speaker 2014 cavity speaker, 1W @ 8Ω Sampling Rate 16KHz to 64KHz Standby Current DC 3.3V / 3.36mA Operating Current DC 3.3V / 14.84mA Operating Temperature 0 to 40°C Product Size 24.0 × 24.0 × 14.1mm Product Weight 6.5g Package Size 85.0 × 65.5 × 15.0mm Gross Weight 12.5g Applications Atomic Voice Base is a practical choice for embedded voice interaction, smart home voice control, custom voice assistant terminals, and compact M5Stack audio projects. M5Stack's own materials show it used with AtomS3R for Home Assistant voice assistant, OpenAI-based voice assistant, and XiaoZhi voice assistant workflows. Home Assistant voice assistant nodes with AtomS3R OpenAI voice assistant and embedded real-time voice interaction Wake-word and voice response projects for smart devices Interactive education projects based on the M5 Atom ecosystem Compact IoT audio control terminals with microphone and speaker Related OpenELAB article: How to Build Your Own Personal Voice Assistant Product List 1 × Atomic Voice Base Other Content PinMap Left Signal Pin Pin Right Signal 1 3V3 SCL 2 3 DIN SDA 4 5 LRCK 5V 6 7 DOUT GND 8 9 SCK Hardware reference Practical note: this base is intended to be paired with an M5 Atom host. If you want an all-in-one voice development unit with the controller already onboard, see M5Stack ATOM Voice Smart Speaker Development Kit. Resources Official M5Stack product documentation Atomic Voice Base schematic PDF ES8311 datasheet MEMS microphone datasheet NS4150B datasheet OpenAI Voice Assistant for AtomS3R + Atomic Voice Base Atomic Voice Base XiaoZhi Voice Assistant AtomS3R + Atomic Voice Base for Home Assistant Atomic Voice Base Arduino library Atomic Voice Base UiFlow2 documentation Open RealtimeAPI Embedded SDK Product introduction video OpenAI voice assistant demo video FAQ Does Atomic Voice Base include the main controller?No. Atomic Voice Base is a base module for the M5 Atom series and does not include its own standalone host controller. What is the difference between Atomic Voice Base and ATOM Voice / Atom Echo?Atomic Voice Base provides the microphone, codec, amplifier, and speaker base, while ATOM Voice / Atom Echo is the integrated version with the controller already built in. Can it be used for Home Assistant or OpenAI voice assistant projects?Yes. M5Stack provides official tutorials for Home Assistant, OpenAI voice assistant, and other voice assistant workflows built around AtomS3R + Atomic Voice Base.
