STMicroelectronics STEVAL-VOICE-UI

Overview

STEVAL-VOICE-UI from STMicroelectronics is an Amazon™-qualified voice user interface evaluation kit built around the STM32H753VIT6E ARM Cortex-M7 MCU (2 MB Flash, 1 MB SRAM, LQFP100), Murata 1DX Wi-Fi module (bypass mode), ISSI IS25LP016D 2 MByte NOR Flash, three MP23DB01HP MEMS microphones (36/30 mm spacing), and FDA903D 45 W Class-D automotive audio amplifier driving an 8 Ω loudspeaker. It enables hands-free Alexa® integration for smart home IoT devices.

For engineers reviewing the STEVAL-VOICE-UI datasheet, STEVAL-VOICE-UI pinout, STEVAL-VOICE-UI application, or STEVAL-VOICE-UI equivalent, this kit supports rapid prototyping of AVS-enabled voice interfaces with validated audio front-end processing, wake-word detection, and full Alexa communication stack running entirely from internal memory - no external RAM required.

Technical Context

The kit implements a complete voice acquisition and playback chain: three spatially separated MP23DB01HP microphones feed into the STM32H753's audio peripherals for beamforming and noise suppression; the FDA903D delivers high-efficiency 45 W digital-input audio amplification to an 8 Ω speaker; Murata 1DX provides 2.4 GHz Wi-Fi connectivity in bypass mode, interfaced via SDIO and SPI with ISSI NOR Flash for firmware storage.

Software runs natively on the STM32H753's dual-bank Flash and tightly coupled SRAM, supporting real-time audio processing, Amazon wake word engine, and AVS protocol stack without external memory expansion - enabling cost-optimized, production-ready voice UI reference design.

Key Specifications

Availability

STEVAL-VOICE-UI is available at Aetrix Electronics and suitable for smart home voice assistant development, Alexa Voice Service (AVS) qualification testing, and industrial voice-controlled HMI prototyping requiring stable component supply and full software stack validation.

Supply support for STEVAL-VOICE-UI includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader delivering intelligent power, sensing, connectivity, and microcontroller solutions for industrial, automotive, and consumer applications.

The STEVAL-VOICE-UI belongs to ST's ST evaluation kits product line, designed to accelerate time-to-proof for cloud-connected voice interfaces using ST's high-performance MCUs and certified wireless/audio subsystems.

FAQ

Does STEVAL-VOICE-UI support over-the-air (OTA) firmware updates?

Yes. The kit uses the ISSI IS25LP016D 2 MByte NOR Flash to store both primary firmware and OTA update images. The included SDK implements secure dual-bank update logic compatible with AWS IoT Device Management, allowing verified rollback and signed image validation before activation.

Is the Murata 1DX Wi-Fi module pre-certified for regulatory compliance?

Yes. The Murata 1DX module carries FCC, IC, CE, and TELEC certifications. In bypass mode, the STEVAL-VOICE-UI leverages the module's integrated RF front-end and antenna matching network, eliminating the need for additional RF validation when used per ST's reference layout and antenna placement guidelines.

Can the microphone array be reconfigured for different spacing or count?

Yes. The modular daughter-board architecture separates microphone placement from the main MCU/Wi-Fi/audio board. Schematics and layout files are provided in the official design package, enabling hardware modification for custom 2-, 3-, or 4-microphone configurations with adjustable spacing and orientation.

What audio interfaces does the FDA903D amplifier support on this board?

The FDA903D is configured for I²S input with TDM capability (4-channel), synchronized to the STM32H753's audio clock tree. It accepts 16/24-bit PCM data at sample rates up to 48 kHz, with hardware volume control and mute functionality managed via I²C from the MCU.