Akustica, Inc., a Bosch Group company and provider of MEMS microphones, has added four new high-performance analog microphones to its high definition (HD) voice product line, including the AKU346, the industry’s smallest MEMS microphone to achieve 64dB SNR. Designed to meet the size-performance constraints of smartphones and even the smallest wearables, the new HD voice microphones combine small footprint, high signal-to-noise ratio (SNR), tight sensitivity matching, and a super-wideband frequency response to improve intelligibility and speech-recognition accuracy in consumer-electronic devices.
New innovations in design and manufacturing enable an inherently guaranteed +/-1dB sensitivity matching between microphones. This microphone-to-microphone uniformity, along with the high SNR of the new HD voice microphones, fulfills a critical need for consumer-electronic device manufacturers who incorporate more than one microphone along with noise suppression algorithms into their devices. These algorithms generally rely on well-matched, high-performance microphones for optimization of noise cancellation and speech recognition accuracy.
Particularly challenging use cases for speech recognition are noisy environments and applications where the speaker is far away (>3 feet) from the microphones. In these situations, testing has shown that even a small improvement in SNR (1-2dB) can lead to dramatic improvements in command accuracy rates (>5%). A few percentage points of accuracy can make the difference between speech recognition ubiquity and obsolescence. This has led device manufacturers to continually look for higher performance and more uniform microphones that can meet the needs of their multi-microphone application without incurring the extra costs commonly charged today for binning and sorting after final test.
”The need for the highest-performing multi-microphone solutions is growing rapidly in the smartphone market, where the average number of microphones per phone has been steadily increasing for the last few years,” said Jérémie Bouchaud, director and senior principal analyst, MEMS & Sensors, IHS. ”Today, the use of two microphones has become a standard feature for smartphones. Higher-end phones can have upwards of four microphones, further increasing the need for high SNR and tighter sensitivity matching like that provided by Akustica s new microphones.”
Bouchaud also pointed out that MEMS microphones achieving >64dB SNR comprise the fastest-growing portion of the overall MEMS microphone market and are expected to generate 50 percent of the revenue of this important market segment by 2017.
Read more: MEMS is still on a dynamic growth path
With a footprint of just 6mm2 and an ultra-thin 0.93mm height, the AKU346 utilizes 33 percent less design space than a typical industry standard bottom-port microphone but still achieves a 64dB SNR-making it particularly well suited for use in small wearable accessories such as wired and wireless headsets, smartwatches and glasses.
AKU143, AKU345, AKU344
The AKU143, AKU345, and AKU344 are top- and bottom-port microphones with a higher SNR of 65dB, and are footprint and pin-for-pin compatible with previous generations of Akustica HD voice microphones. The industry standard form factors of all three microphones provide a straightforward path for upgrading performance of current designs.
All four of the new microphones can also support ultrasonic applications such as gesture recognition, gaming, pens and location detection.
Samples of all four new HD voice microphones are available now for customers with mass production planned for Q2 2014.