M5Stack ATOM Voice Smart Speaker Development Kit is a compact ESP32 smart speaker development kit built for voice interaction, audio playback, and AIoT control. This product line is widely known as Atom Echo, while the current official product title uses ATOM Voice. It combines an ESP32-PICO-D4 controller, SPM1423 PDM microphone, NS4168 I2S speaker amplifier, SK6812 RGB LED, and a compact expansion interface inside the classic 24 × 24 × 17 mm ATOM form factor. It is designed for small-footprint voice control, smart speaker, ESPHome, Home Assistant, and cloud-connected ESP32 voice assistant projects. It can play designated streaming media over Wi-Fi, supports audio input and output, and keeps the control flexibility of the ATOM family for connected sensors and external devices. Features ESP32-PICO-D4 platform for compact Wi-Fi voice and control projects. Built-in microphone and speaker using SPM1423 (PDM) and NS4168 (I2S). Built-in STT workflow support for voice interaction projects. Wi-Fi audio and connected control for smart interaction and networked speaker use. SK6812 RGB LED for visible status indication. IR-TX, button, and reset button for local control and integration. GROVE / HY2.0-4P expansion interface for external device connection. Arduino and ESP-IDF / ADF support for flexible development. M2 mounting hole on the rear for easier installation. Specifications Specification Parameter SoC ESP32-PICO-D4, 240 MHz, Dual Core, Wi-Fi Flash 4 MB Wireless Wi-Fi IEEE 802.11 b/g/n Interface 1 × IR-TX, 1 × Button, 1 × Reset Button PinOut G21 / G25 / 5V / GND, 3V3 / G22 / G19 / G23 / G33 RGB LED SK6812 Speaker 0.8 W / NS4168 (I2S) Microphone SPM1423 (PDM) Enclosure Plastic (PC) Product Weight 5 g Gross Weight 10 g Product Size 24 × 24 × 17 mm Package Size 85 × 65 × 17 mm Applications The ATOM Voice is a good fit for smart home voice control, ESPHome voice nodes, Home Assistant experiments, Wi-Fi speaker projects, interactive IoT devices, and compact voice-triggered automation systems. M5 also positions it for AWS, Baidu, and other cloud-connected voice workflows. Voice control for compact embedded projects Storytelling and interactive audio demos ESP32 AIoT prototyping with microphone and speaker Smart home interaction with ESPHome or Home Assistant Small connected speaker and wireless audio concepts Product List 1 × ATOM Voice Smart Speaker Development Kit Other Content Important notes Reserved pins: G19 / G22 / G23 / G33 are predefined and should not be reused. Audio playback precautions: avoid outputting a DC signal through the I2S channel, playing white noise for long periods, or playing full-scale square-wave audio. Physical installation: the compact enclosure and rear mounting hole make it easier to integrate into small smart interaction projects. Related reading M5Stack ATOM Echo: Compact, Powerful Smart Speaker Kit OpenELAB Wiki: M5Stack ATOM Echo Smart Speaker Development Kit Resources M5Stack ATOM Echo Documentation M5Stack Arduino Guide M5Stack ESP-IDF Guide M5Burner Guide M5Stack Home Assistant Overview M5Stack Hardware Design Files FAQ Is this the same product family as Atom Echo?Yes. This compact M5Stack voice development kit is commonly known as Atom Echo, while the current official product title uses ATOM Voice. Can it be used with Home Assistant or ESPHome?Yes. M5 presents this product family for ESPHome and Home Assistant based voice and smart interaction workflows. What are the main hardware highlights?The key hardware pieces are ESP32-PICO-D4, SPM1423 microphone, NS4168 speaker amplifier, SK6812 RGB LED, and the compact 24 × 24 × 17 mm ATOM body. Certificates and Compliance Documents Available certification and compliance documents for this product can be reviewed as PDF files below. C02-C EMC final Document RED Document RED Document RSHD200103001-01A_EMC-EMI-EMS_EN55032 EN55035 Document RSHD200103001-01B_EN300328_2.4G Wi-Fi Document RSHD200103001-01C_EN300328_V2.2.2_BLE Document RSHD200103001-01D_EN300328 V2.2.2_BT3.0 Document RSHD200103001-01E_EN62311 Document RSHD200103001-02_EN301489-1-17 Document RSHD200103001-SF EN62368-1 Safety report Document
