STMicroelectronics STEVAL-MKI139V4

Overview

STEVAL-MKI139V4 from STMicroelectronics is a microphone coupon evaluation board hosting four MP23AB01DM analog MEMS microphones, each with -38 dBF_S sensitivity (±1 dB), 65 dB SNR, and 135 dBSPL acoustic overload point. It operates from 2.3–3.6 V, supports 100 Hz–10 kHz frequency response, and enables individual PCB detachment for isolated microphone characterization in audio front-end validation.

For engineers reviewing the STEVAL-MKI139V4 datasheet, STEVAL-MKI139V4 pinout, STEVAL-MKI139V4 application, or STEVAL-MKI139V4 equivalent, this board provides verified analog output routing, THD-limited performance at 94/130 dBSPL, RoHS-compliant layout, and direct interface capability to ADC inputs or op-amp preamplifier stages in voice capture and far-field audio systems.

Technical Context

The board implements a 4-microphone coupon architecture with independent bottom-port MP23AB01DM devices, each terminated with 1 μF DC-blocking capacitors and 270 pF high-frequency filtering on differential outputs. Power delivery uses local 100 nF decoupling per microphone to maintain supply stability under dynamic acoustic loads.

All microphones share a common 2.3–3.6 V V_DD rail and ground plane; output signals are fully differential (OUT+, OUT−), enabling noise-rejecting connection to instrumentation amplifiers or differential-input ADCs without single-ended conversion.

Key Specifications

Availability

STEVAL-MKI139V4 is available at Aetrix Electronics and suitable for voice interface development, far-field beamforming prototyping, and MEMS microphone qualification requiring stable component supply and traceable ST original hardware.

Supply support for STEVAL-MKI139V4 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, designing and manufacturing microcontrollers, sensors, power ICs, and analog products for industrial, automotive, and consumer applications.

This board belongs to ST's STEVAL sensor evaluation platform family, engineered to accelerate validation of ST MEMS microphones in real-world acoustic environments with minimal external circuitry.

FAQ

What is the electrical interface configuration of each MP23AB01DM on STEVAL-MKI139V4?

Each microphone uses a fully differential analog output (OUT+, OUT−) with no internal biasing-external DC-blocking capacitors (1 μF) and termination resistors are provided. The board does not include integrated preamplification; outputs require external gain stages before ADC sampling.

Can STEVAL-MKI139V4 be used for beamforming algorithm development?

Yes-the four spatially separated, identically biased MP23AB01DM microphones provide synchronized analog outputs with matched sensitivity (±1 dB) and phase response, enabling time-difference-of-arrival (TDOA) estimation and fixed/dynamic beamformer implementation in MATLAB or Python-based toolchains.

Is external power regulation required when using STEVAL-MKI139V4?

No-board-level power filtering uses 100 nF ceramic capacitors per microphone and accepts 2.3–3.6 V directly. However, a low-noise, well-regulated source is recommended to avoid introducing supply-induced modulation into the analog audio path.

Does STEVAL-MKI139V4 include calibration data for individual microphones?

No-each MP23AB01DM device is uncalibrated at board level. Sensitivity tolerance (±1 dB) and SNR (65 dB) are guaranteed per datasheet, but unit-to-unit gain matching relies on factory binning; users must perform acoustic calibration if absolute SPL measurement accuracy is required.