STMicroelectronics STEVAL-MKI155V2

Overview

STEVAL-MKI155V2 from STMicroelectronics is a microphone coupon daughterboard designed for acoustic performance evaluation of four MP34DB02 digital MEMS microphones, supporting PDM output, 1.64–3.6 V supply, 120 dBSPL acoustic overload point, and -26 dBFS sensitivity. It interfaces directly with the STEVAL-MKI126Vx Smart Voice kit for beamforming and voice capture prototyping.

For engineers reviewing the STEVAL-MKI155V2 datasheet, STEVAL-MKI155V2 pinout, STEVAL-MKI155V2 application, or STEVAL-MKI155V2 equivalent, key selection criteria include PDM interface compatibility, multi-microphone spatial layout, supply voltage range, SNR (62.6 dB), and mechanical decoupling capability via detachable PCBs.

Technical Context

The board implements a fixed-layout 4-microphone array with individual bottom-port MP34DB02 devices mounted on separate detachable sub-PCBs, enabling acoustic isolation testing. Each microphone delivers single-bit PDM output synchronized to an external clock, requiring no on-board decimation or digital signal processing.

Power delivery is routed from the host STEVAL-MKI126Vx board via a single 1.64–3.6 V rail; no local regulation or level-shifting circuitry is present. The coupon architecture supports rapid substitution and comparative measurement across identical MEMS elements under matched acoustic conditions.

Key Specifications

Availability

STEVAL-MKI155V2 is available at Aetrix Electronics and suitable for voice interface development, multi-microphone beamforming validation, and MEMS microphone acoustic characterization requiring stable component supply and consistent mechanical layout.

Supply support for STEVAL-MKI155V2 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 headquartered in Geneva, specializing in microcontrollers, sensors, power ICs, and analog/mixed-signal solutions for automotive, industrial, and consumer applications.

This board belongs to ST's STEVAL sensor evaluation platform family, engineered to accelerate prototyping of intelligent sensing subsystems-particularly voice, motion, and environmental sensing-with plug-and-play compatibility across host kits.

FAQ

Does STEVAL-MKI155V2 include on-board PDM-to-PCM conversion?

No. The board provides raw PDM output from each MP34DB02 microphone only. Decimation and digital filtering must be performed externally-typically by the host STEVAL-MKI126Vx board's microcontroller or dedicated audio processor. No clock generation, FIFO, or sample-rate conversion circuitry is integrated.

Can STEVAL-MKI155V2 operate independently without STEVAL-MKI126Vx?

No. It is a daughterboard with no onboard power regulation, clock source, or host interface logic. It requires connection to the STEVAL-MKI126Vx Smart Voice kit for power, clock, and data routing. No standalone operation or USB/serial interface is supported.

What mechanical mounting options does the board support?

The board uses standardized 2.54 mm pitch headers for mating with STEVAL-MKI126Vx and includes four M2 mounting holes aligned to common microphone array geometries. Each MP34DB02 sub-PCB detaches via breakaway tabs, allowing individual placement in custom enclosures or acoustic test fixtures.

Is the MP34DB02 sensitivity calibrated per unit on STEVAL-MKI155V2?

No factory calibration is performed per board. All four microphones are from the same production lot and share nominal -26 dBFS sensitivity, but unit-to-unit variation up to ±1.5 dB is specified in the MP34DB02 datasheet. System-level calibration is required for beamforming accuracy.