Recently, AAC Technologies has released a new “barometric pressure and microphone combo sensor”, which innovatively integrates an air pressure sensor and a microphone in one package to deliver high-definition voice and realize high-precision air pressure sensing at the same time. This product is equipped with AAC Technologies’ proprietary and self-made low-noise and high-performance microphone chips to make voice clearer. In terms of air pressure sensing, it can accurately measure centimeter-level height changes, precisely pinpoint the number of floors, and even accurately identify the height change of stair steps.
Currently, this innovative product has been mass-produced and applied in smart wearables.
Self-made low-noise high-performance microphone chip
In terms of sound pickup, this 2-in-1 sensor integrates AAC Technologies’ self-made low-noise high-performance microphone chip. The high signal-to-noise ratio (SNR) as high as 66dB helps with clearer speech input in speaking and video chatting scenarios. The 130dBSPL acoustic overload point (AOP) can efficiently address the overdrive issue that may occur in noisy environments or outdoor windy environments and deliver a better hearing experience.
Accurately measures height changes as small as 5cm
As for air pressure sensing, it adopts a high-performance air pressure sensor chip that gives the best measuring performance in the measurement range of 300 to 1100hPa. Thanks to the high precision of the air pressure sensor, this 2-in-1 sensor of AAC Technologies can accurately measure height changes as small as 5cm, so as to provide accurate data and information for indoor and outdoor navigation, height, floor measurement and positioning, as well as other applications. The air pressure sensor can compensate for GPS errors and provide accurate height and floor positions even in indoor environments or subways with poor signals.
(Measured data of floors)
The sensor can accurately identify floors by sensing changes in air pressure
(Measured data of stair steps)
The sensor can accurately measure centimeter-level height changes and identify the height of stairs
According to data from Counterpoint, the global shipment of smart watches in 2021 was 128 million, a YOY increase of 28.31%. In recent years, people have paid unprecedentedly high attention to their health. Smart watches are constantly iterating based on users’ needs, and their functions are growing more and more diversified. Apart from basic functions like voice, imaging, and positioning, more health and detection functions are being added, such as heart rate monitoring and blood pressure monitoring. Function upgrades can never be achieved without the support of sensors. However, as smart watches have a compact stacking space, the addition of sensors will pose a great challenge for the size of sensors and their layout in devices.
According to Wu Zhijiang, the general manager of the Sensor and Semiconductor Business Unit of AAC Technologies, this 2-in-1 hybrid sensor features a PDM output and package size of 4.8 × 2.6 × 1.05mm, which is 13% smaller than independent air pressure sensors and microphones (on the motherboard), giving more layout flexibility and a more ample room for adjustment. In addition, in terms of product design, the air pressure sensor and the microphone share one opening in the 2-in-1 sensor, which significantly simplifies the overall structure, the circuit structure, the peripheral mechanical enclosure, and the waterproof design, effectively improving production efficiency and saving processing costs.
According to the product’s introduction, when matched with GPS, gyroscope, accelerometer and other positioning chips and supported by relevant algorithms, this product can be widely applied in accurate height detection for smart watches and mobile phones, indoor and outdoor navigation, sports data recording, and even fall detection, thus improving the user experience of terminal devices.
Wu Zhijiang said the smart sensing technology with MEMS and advanced sensors as the core lays the foundation for the upcoming era of intellectualization. Since the mobile 5G, IoT, and other industries are springing up at a faster pace, MEMS sensors are replacing traditional mechanical sensors and demonstrating huge market potential. Domestic sensor enterprises will embrace a golden opportunity for industrial upgrades by virtue of technological accumulation and the need of downstream clients for homemade parts. As a technical leader of electronic components in China, AAC Technologies will facilitate the development of the complete eco-chain, from chips to products and to solutions in the future at the advantage of its core technologies, and create better perceptual experiences for users of smart terminals.