Summary of Industry’s Most Sensitive MEMS Mic
Vesper Technologies introduced the VM101, a high-definition MEMS microphone with a 68dB signal-to-noise ratio, surpassing current industry standards. Utilizing piezoelectric aluminum-nitride crystals in a unique four-triangle diaphragm design, the device offers superior sensitivity and noise cancellation. The company plans to ship wafers containing these microphones to OEMs, who will add an analog ASIC for final packaging. Future roadmaps include higher SNR models by 2018.
Parts used in the Vesper VM101 Project:
- Piezoelectric aluminum-nitride wurtzite crystals
- Four-triangle diaphragm forming a square
- Analog application specific integrated circuit (ASIC)
- Standard 3.35-by-2.5-by-1 millimeter package
- MEMS wafers containing tiny 0.5-by-0.5-by-0.25 microphones
PORTLAND, Ore. — In its rush to get to market “while the iron is hot,” Vesper Technologies Inc. (Boston) has announced what it still claims is the industry’s highest signal-to-ratio (SNR) for a high-definition (HD) microelectromechanical system (MEMS) microphone, even though it is scaled back to 68dB rather than the astounding 70dB SNR MEMS mic they previously promised.
“Our roadmap now calls for the 70dB version in 2016, followed by an ultra-miniature, low-power 72dB model in 2017 and a 75dB signal-to-noise ratio model by 2018,” Vesper Chief Executive Officer Matt Crowley told EE Times. “Even at 68dB, our current model VM101 almost doubles the performance compared to current high-end 65 dB SNR capacitive MEMS microphones.”
The key to Vesper’s high SNR is its use of the piezoelectric aluminum-nitride wurtzite crystals in its unique four-triangle diaphragm forming a square (see photo) with the sound squeezing through the gaps between the triangles, causing them to vibrate thus creating a piezoelectric current. According to Vesper, the sensitivity of its piezoelectric material doubles the distance that sounds can be heard, does dramatic noise cancellation that improves the clarity of phone conversations and minimizes the errors made during voice-commands. And when used in multi-mic set-ups, its high-SNR mics can more easily form beams directly to the person speaking — what retailers call “audio zoom” — to further increase the accuracy of voice-enabled applications, according to Vesper.
Crowley reiterated that Vesper was sticking to its business plan of supplying MEMS wafers full of tiny 0.5-by-0.5-by-0.25 microphones to top tier original equipment manufacturers (OEMs) to which they add a single-ended analog application specific integrated circuit (ASIC) and can package in a standard 3.35-by-2.5-by-1 millimeter package (making them a drop-in replacement for capacitive MEMS microphones).
Selling wafers only is the strategy that Infineon uses with its MEMS mics, allowing it to capture a vast swath of the worldwide market including MEMS mic manufacturers AAC, Goertek, BSE, Hosiden and Gettop, all of which use Infineon MEMS dies today. The addition of Vesper’s HD wafer-only sales strategy should boost its units-shipped over calling on individual smartphone, wearable and Internet-of-Things (IoT) makers, which IHS predicts will grow to 5.4 billion units reaping $1.3 billion by 2017 (see figure).
For more detail: Industry’s Most Sensitive MEMS Mic
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What is the current signal-to-noise ratio of the Vesper VM101?
The current model VM101 has a signal-to-noise ratio of 68dB. -
How does the Vesper diaphragm design work?
Sound squeezes through gaps between four triangles forming a square, causing them to vibrate and create a piezoelectric current. -
Can this microphone be used as a drop-in replacement?
Yes, when packaged in a standard 3.35-by-2.5-by-1 millimeter size, it serves as a drop-in replacement for capacitive MEMS microphones. -
What benefits does the high SNR provide for voice commands?
It performs dramatic noise cancellation that improves clarity and minimizes errors made during voice commands. -
How does the multi-mic setup improve audio accuracy?
High-SNR mics can form beams directly to the speaker, a feature retailers call audio zoom, increasing accuracy. -
What is Vesper's business strategy regarding sales?
Vesper supplies MEMS wafers full of microphones to top tier original equipment manufacturers rather than selling finished units directly. -
When is the 70dB version of the microphone expected?
The roadmap calls for the 70dB version to be available in 2016.
