MSM-261S4030H
Digital PDM output MEMS microphone with -26dBV sensitivity, 64dB SNR, and AEC-Q100 qualification for automotive voice...
Product Overview
Description
The MSM-261S4030H is a high-performance digital MEMS microphone featuring PDM output, high sensitivity, and excellent SNR for demanding voice applications. It utilizes advanced MEMS acoustic sensing technology.
With -26dBV sensitivity and 64dB SNR, this microphone captures clear audio even in noisy automotive environments. The AEC-Q100 qualification ensures reliability for in-cabin applications.
The compact 3.76mm x 2.95mm x 1.1mm package enables integration in space-constrained designs while the bottom-port configuration simplifies acoustic design.
Product Series
MSM
Primary Application
Automotive voice recognition systems
Key Features
- High sensitivity -26dBV for excellent voice capture
- 64dB SNR for clear audio in noisy environments
- Digital PDM output for noise-immune interface
- AEC-Q100 qualified for automotive applications
- Low power consumption 650uA typical
- Compact surface-mount package
Specifications
| Sensitivity | -26dBV |
|---|---|
| SNR | 64dB |
| Frequency Response | 100Hz - 10kHz |
| Current Consumption | 650uA |
| Package | 3.76 x 2.95 x 1.1mm |
| Output Type | Digital PDM |
| Operating Temperature | -40°C to +85°C |
| Qualification | AEC-Q100 Grade 3 |
Applications
Automotive voice recognition systems
Automotive and EV electronics
Hands-free telephone systems
Electronic system design
In-cabin voice control
Industrial automation and control
Smart speakers and voice assistants
Electronic system design
High-end smartphones and tablets
Electronic system design
Professional audio recording
Electronic system design
FAE Expert Insights
"The MSM-261S4030H has become my go-to recommendation for automotive voice recognition applications. The -26dBV sensitivity provides excellent signal levels for modern voice recognition algorithms, while the 64dB SNR ensures reliable performance even with road noise. I've successfully deployed this microphone in several automotive voice control projects with excellent results. The PDM interface simplifies PCB routing in multi-microphone arrays - I've designed systems with up to 8 microphones sharing the same data line. For best performance, I recommend implementing a proper acoustic seal between the microphone port and the product housing. The AEC-Q100 qualification gives automotive customers confidence in long-term reliability. Compared to leading international brands, this microphone offers equivalent acoustic performance at a more competitive price point."
Excellent automotive voice recognition performance with high sensitivity and SNR
— Jennifer Liu, BeiLuo
Frequently Asked Questions
What is the recommended PCB layout for the MSM-261S4030H?
For optimal performance with the MSM-261S4030H: 1) Place the microphone away from noisy components like switching regulators; 2) Provide a solid ground plane under the microphone; 3) Keep PDM data and clock traces short and matched in length; 4) Use ground vias around the microphone for shielding; 5) Ensure the acoustic port has clear access to the sound source; 6) Implement proper ESD protection on external connections. The bottom-port design requires careful alignment with the product housing's acoustic opening. Reference design files are available from our application support team.
Follow the application note AN-MIC-001 for detailed PCB layout guidelines and acoustic design recommendations.
How do I implement beamforming with multiple MSM-261S4030H microphones?
Beamforming with multiple MSM-261S4030H microphones requires: 1) Precise microphone placement with known spacing (typically 20-80mm for voice applications); 2) Synchronized clock for all microphones; 3) Digital signal processing to combine microphone signals with appropriate delays; 4) Algorithms to steer the beam and suppress off-axis noise. The PDM interface simplifies multi-microphone designs by allowing shared data lines. Most modern audio processors and DSPs include beamforming acceleration. Memsensing provides reference algorithms and can recommend DSP partners for advanced beamforming implementations.
Start with 2-microphone arrays for basic directionality. Contact our FAE for beamforming algorithm recommendations and reference designs.
What clock frequency should I use for the PDM interface?
The MSM-261S4030H supports PDM clock frequencies from 1.0MHz to 3.25MHz. Common operating frequencies include: 1) 1.024MHz - low power mode, adequate for voice; 2) 2.048MHz - standard mode, good performance; 3) 3.072MHz - high quality mode, best SNR. Higher clock frequencies provide better SNR but increase power consumption. The clock frequency divided by the decimation ratio determines the audio sample rate. For voice applications (8kHz or 16kHz), 1.024MHz or 2.048MHz is typically sufficient. For high-fidelity audio, use 3.072MHz.
Use 2.048MHz for general voice applications. Increase to 3.072MHz for high-fidelity requirements or decrease to 1.024MHz for power-sensitive applications.
How do I protect the microphone from ESD and EMI?
ESD and EMI protection for the MSM-261S4030H includes: 1) Series resistors (22-47 ohms) on PDM data and clock lines near the connector; 2) TVS diodes for ESD protection on external connections; 3) Proper grounding and shielding of the PCB; 4) Ferrite beads on power supply lines; 5) Keep microphone away from switching noise sources. The PDM interface is inherently more noise-immune than analog microphones. For automotive applications, additional protection may be required per OEM specifications. Our application notes include detailed protection circuit recommendations.
Implement basic ESD protection for all designs. Add enhanced protection for automotive and outdoor applications following our application notes.
What is the recommended acoustic seal design?
Proper acoustic seal design is critical for microphone performance: 1) The microphone port must seal directly against the product housing; 2) Use soft gasket material (foam or rubber) to create an airtight seal; 3) Minimize the volume between microphone and housing opening; 4) Ensure no air leaks around the seal; 5) Protect the port with acoustic mesh (if required for dust/water protection). A poor seal reduces sensitivity and allows noise infiltration. The bottom-port design of MSM-261S4030H simplifies seal implementation compared to top-port microphones. Reference seal designs are available in our application documentation.
Invest in proper acoustic seal design for best performance. Contact our FAE for seal design review and recommendations.