A smart microphone is an innovative IC based on MEMS technology, which realizes high-quality sound and includes interesting speech recognition features for consumer audio applications. You’ll find them today in your smartphones, laptops, and tablets. My children have found the smart mics on our home laptop, much to my ears’ dismay.
In 1989, long before my kids were born, the journey to smart audio began, led by big companies in the electronics field with a vision for the future of the microphone. Yet it stalled for decades in R&D, sidelined by lack of money to invest in the research, lack of patience to keep reworking the problems, and low manufacturing yields when the designs were successful.
For those electronics companies that remained committed to the game, the market scenario for audio smart microphone ICs, known as MEMS microphones, is now gaining importance in the semiconductor market (see Figure 1):
According to SAR Insight & Consulting in a recent EE Times Europe article, “Such microphones will have almost no share in a MEMS microphones market in 2016 worth about $1.04 billion. However by 2020 the market share will be $300 million out of a total of about $1.62 billion, SAR estimates. Almost 6 billion MEMS microphones are expected to ship in 2020 for use in a wide range of equipment.”
The forecast of revenues of smart microphones up to 2020 (source: EE Times Europe)
Among the companies mass producing MEMS microphones is STMicroelectronics, which announced a collaboration with the Soundchip Company to produce smart audio systems based on MEMS microphones (see Figure 2):
STMicroelectronics’ MEMS microphones are inside Soundchip devices to realize high quality audio systems (source: STMicroelectronics web)
If you’ve used a speech recognition system you may have concluded that electronic devices are becoming more intuitive—speech recognition engines automatically provide real time assistance when the user makes a request—at a word, the connected systems can turn on and off the lights of a smart house. My kids have way too much fun with this feature, calling for the lights to go on and off at the most inconvenient times. Voice recognition may be the next big thing – allowing only certain voices access to certain controls… Anyway, this feature makes this solution optimal for IOT (Internet of things) technology applications. Wearable applications are another possible field for MEMS microphone expansion—a connected wearable taking voice commands to activate a home security system, perhaps?
“We believe in a future of smart, software-enabled wearable sound devices, which respond to their environment and use-case to improve audio quality and speaking comfort.” (See Figure 3)
Soundchip’s device features allows an unprecedented sound experience (Source: soundchip.ch)
Let’s look at the basic principle of a MEMS microphone, using ST’s MP23AB01DH IC as an example:
“The MP23AB01DH is a compact, low-power microphone built with a capacitive sensing element and an IC interface. The sensing element, capable of detecting acoustic waves, is manufactured using a specialized silicon micromachining process to produce audio sensors.” (See Figure 4)
The diagram of the typical application circuit of the MEMS microphone MP23AB01DH from STMicroelectronics (source: ST online catalog)
STMicroelectronics is also a major player for another personal favorite smart audio application—radio broadcast systems—and ST chips have been used for Sirius, a satellite music provider (See Figure 5):
The Sirius satellite radio project, the Sirius radio kits contain ST baseband IC and ST RF Front End IC (Source: SiriusXM satellite radio)
What do you think of the Smart Audio concept? Is it effective? How do you see the Smart Audio scenario playing out in the near future?