STSmartVoice demonstration board based on MP34DT01

The STEVAL-MKI126V3 demonstration board allows the connection of up to six microphones using the sockets provided, or through the connection of a dedicated six-microphone array.

The digital interface of the board allows the interfacing of the MIC output to the most widely used audio receivers and digital amplifiers, or permits evaluation of the MIC with generic audio measurement equipment. The filtered PWM signals allow the connection of a headset to listen to audio received through the microphones.

The fully digital path ensures a high level of processing with sound preconditioning, filtering and voice enhancement.

The main function of the STEVAL-MKI126V3 is to convert the PDM signals from the microphones into more common I2S and PWM signals.

The I2S signal is routed both on a general and interface connector. appropriately filtered PWM signals provide an analog interface.

The STEVAL-MKI126V3 is equipped with two MP34DT01 microphones and an STA321MPL scalable digital microphone processor.

Key Features

  • 2 on-board MEMS MP34DT01 microphones on board
  • Capable of driving up to 6 digital MEMS microphones
  • 3 independent I2 S outputs
  • Up to 10 independent 32-bit user programmable biquads per channel
  • The demonstration board is fully configurable with:
    • STEVAL-MKI129V1/V2/V3
    • STEVAL-MKI131V1/V2/V3
    • STEVAL-MKI116V1
    • STEVAL-MKI117V1/V2
    • STEVAL-CCA035V1
  • Controllable via APWorkbench software suite
  • RoHS compliant




Technical Documentation

Product Specifications
Description Version Size
DB1757 DB1757: STSmartVoice demonstration board based on MP34DT01 2.0 292 KB
Application Notes
Description Version Size
AN4227 AN4227: Audio hub demonstration kit supporting the M45DT02, MP34DB01, and MP34DT01 microphones 1.0 1 MB
AN4146 AN4146: STSmartVoice demonstration board STEVAL-MKI126Vx 2.0 3 MB

Hardware Resources

Board Manufacturing Specifications
Description Version Size
STEVAL-MKI126V3 gerber files 1.0 472 KB
Bill of Materials
Description Version Size
Schematic Pack
Description Version Size
STEVAL-MKI126V3 schematics 2.0 96 KB


License Agreement
Description Version Size
Evaluation products license agreement 1.4 128 KB

Tools and Software

Development Tools
Software Development Tools
Support & Community

Sample & Buy

Part Number Marketing Status Unit Price (US$) * Quantity Core Product ECCN (EU) ECCN (US) Country of Origin More info Order from ST Order from Distributors
STEVAL-MKI126V3 NRND 106 1 STA321MPL; MP34DT01 NEC EAR99 - MORE INFO No availability reported, please contact our Sales office

(*) Suggested Resale Price per unit (USD) for BUDGETARY USE ONLY. For quotes, prices in local currency, please contact your local ST Sales Office  or our Distributors

Quality & Reliability

Part Number Marketing Status Package Grade RoHS Compliance Grade Material Declaration**
STEVAL-MKI126V3 NRNDCARDIndustrialEcopack2

(**) The Material Declaration forms available on may be generic documents based on the most commonly used package within a package family. For this reason, they may not be 100% accurate for a specific device. Please contact our sales support for information on specific devices.