In 1883, university professor Warren Seymour Johnson (1847-1911) obtained his first patent for the “Electric Remote Control Thermometer,” which could automatically adjust room temperature, creating a more energy-efficient and comfortable building environment. This temperature control system has since been widely used in most high-rise landmark buildings around the world. In 1885, Professor Warren Johnson and another founder of the company, William Plankinton, officially established Johnson Controls, the predecessor of Johnson Controls International.
The temperature regulation system from 1883
From the story of Johnson Controls, we can see that the innovation of end products is inseparable from the differentiated innovation of sensors, and today this relationship is becoming increasingly close. For example, in smartphones, more people care about photographic capabilities (image sensors), while in autonomous vehicles, the competition is about perception capabilities (various active and passive sensors), and maintenance monitoring systems popular in factories also rely on various sensors (MEMS, pressure, vibration, etc.).
For over a century, sensors have continuously improved the convenience of people’s work and life. With the development of semiconductor technology and IoT technology, new opportunities and missions have been given to the sensor market, with smaller, more precise, more energy-efficient, and cheaper sensors being rapidly developed.
As one of the most important components of the Internet of Things, and also the starting point of IoT technology, sensors can not only realize data collection from the real world but also provide a new way of human-computer interaction. From voice recognition to gesture recognition, it can be said that a smart, digital home and society cannot be separated from the sensors that are spread everywhere.
The 2021 IoT sensor market report from Marketsandmarkets also confirms this trend, indicating that the IoT sensor market size is expected to grow from $8.4 billion in 2021 to $29.6 billion by 2026, with a compound annual growth rate of 28.6% during the forecast period.
Forecast of market development for several important sensors
Data source: Infineon
As a company that has accumulated 40 years of experience in sensor product R&D and has a rich portfolio of sensing technologies, Infineon is naturally well-prepared to respond to this rapidly growing market. In order to make the concept of sensors more intuitive and memorable, Infineon chose to use the five senses of the human body to metaphorically illustrate its rich XENSIV sensor product portfolio. This includes visual represented by millimeter-wave radar and 3D ToF, auditory represented by MEMS microphones, olfactory represented by CO2 sensors, and tactile represented by pressure sensors, among others. This metaphor not only proves that Infineon’s sensors achieve full coverage of human perception but also indicates that Infineon’s high-performance sensors can truly endow machines with human capabilities.
“The five senses” are sensors
In the past decade, Infineon’s sensor shipments have exceeded 20 billion units, covering a wide range of applications including automotive, industrial, and IoT. Why can Infineon always lead the sensor market? This article attempts to deconstruct Infineon’s innovations in sensors from multiple dimensions, providing insight into its deep reasons for continuing to lead the development of sensors in the IoT era.
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Innovative Combination
The first type of innovation comes from combination. The concept of combinatorial innovation comes from Peter Drucker, which means achieving innovation through the recombination of basic elements. Infineon’s XENSIV™ PAS CO2 sensor is an example of innovation achieved through this method, combining Infineon’s highly sensitive MEMS microphones, microcontrollers, MOSFETs, and other technologies to achieve the best cost-performance ratio for CO2 sensing solutions.
The indoor CO2 concentration has a crucial impact on human health. Research shows that when the concentration is too high, it can cause dizziness. Furthermore, in poorly ventilated environments, it also increases the risk of spreading various viruses such as COVID-19. Therefore, effectively detecting indoor CO2 concentrations to automatically execute ventilation can ensure human health in multiple ways.
Currently, there are many methods for CO2 concentration measurement. One of the mainstream methods is non-dispersive infrared technology (NDIR), which measures the specific concentration of CO2 using its physical characteristics of absorbing infrared light at a wavelength of 4.26μm.
Photoacoustic spectroscopy technology utilizes the photoacoustic effect of solids discovered by Bell in 1880. The heat generated by gas absorbing light energy is expressed in the form of sound pressure, and by testing the sound pressure with a microphone, the CO2 content can be detected through its sound pressure characteristics.
Photoacoustic spectroscopy technology has advantages such as high sensitivity, good selectivity, long life, and small measurement volume, but it is costly, making it difficult to popularize in the cost-sensitive IoT market. Infineon has optimized the MEMS microphone for low-frequency signal acquisition, achieving a lower cost microphone, thus significantly reducing acquisition costs.
Additionally, to facilitate user usage, Infineon has integrated the XENSIV™ PAS CO2 sensor with a photoacoustic (PAS) transducer (detector, infrared light source, and filter), a microcontroller for signal processing and algorithms, and a MOSFET to drive the infrared light source, all on a single PCB. This provides customers with convenient development and production in a modular SMD (Surface-Mounted Device) packaging format. The integrated microcontroller has built-in ppm concentration calculation and advanced compensation and configuration algorithms, ensuring the product has long-term stable and reliable characteristics, as well as supporting a rich set of peripheral interfaces (UART, PWM, I2C, etc.).
It is worth mentioning that the CO2 sensor, in addition to being used for indoor air quality monitoring, has also been announced by Infineon to collaborate with Rainforest Connection to plan to use the CO2 sensor for forest fire prevention and other intelligent IoT applications.
CO2GO selects Infineon technology to develop portable low-power CO2 sensors
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Innovation Migration
The second type of innovation is migration. A current prime example is the migration of data to the cloud, which has created rich industrial demand. As one of the main suppliers of automotive pressure sensors, Infineon has traditionally used piezoresistive sensors, which are widely applied in various fields including pressure gauges for liquids or gases inside vehicles, side airbags, pedestrian protection, tire pressure, etc. Today, more and more consumer products need tactile feedback to sense pressure. With the basic principles unchanged, migratory innovation can quickly expand the application scenarios of pressure sensors.
Piezoresistive sensors have proven their high reliability through decades of automotive installations by Infineon. However, piezoresistive sensors also have inherent disadvantages, such as their MEMS area being too large, high noise, and high power consumption, making them difficult to apply in consumer IoT products. Therefore, Infineon migrated its signal conditioning technology for pressure sensors to the consumer domain, and replaced resistive MEMS with capacitive MEMS, achieving smaller area, higher accuracy, and lower power consumption. Due to the smaller area, it can also integrate ASIC with MEMS, further reducing system size.
By migrating pressure sensors to IoT and consumer domains, Infineon can flexibly apply them in various scenarios that require collecting air pressure and wind speed data, and even detect fall actions. The specific product forms range from smartphones, smartwatches to predictive maintenance for HVAC systems, air conditioners, and even drones.
Infineon DPS310 pressure sensor application scenarios
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Innovative Process
The third type of innovation is process innovation. The process is the core competitiveness of semiconductors, without a doubt. It is well known that CMOS technology is the longest-lasting, most commercialized, and lowest-cost technology in the semiconductor industry.Infineon’s latest millimeter-wave radar sensor is developed based on CMOS technology, which has many advantages such as low cost, high integration, low power consumption, and small size, making it very suitable for consumer applications.
Currently, Infineon’s millimeter-wave radar sensor for the IoT market operates in the 60GHz frequency band, with up to 7GHz of ultra-wide bandwidth available for various short-range detection, supporting applications from personnel tracking to image segmentation. Due to its high precision characteristics, it can even be used for applications such as gesture recognition, material classification, and vital sign detection (breathing, heartbeat, and even blood pressure). From Google Pixel 4 smartphones to Samsung TVs, they all use Infineon’s millimeter-wave radar sensors.
Millimeter-wave radar does not collect specific facial information, making it particularly suitable for applications in family IoT environments with high privacy requirements. For example, Infineon’s partner Qinglei Technology has developed the “Beijian Smart Health Life Support System,” which utilizes millimeter-wave chips to accurately detect vital signs such as breathing and heart rate in a non-contact manner, as well as some basic motion recognition. This improves people’s sleep health, provides risk warnings for potential diseases, and can monitor falls in the elderly.
Another typical application of millimeter-wave radar in IoT is presence detection. For example, when entering a home, the air conditioning, lighting, and television will turn on, and when no one is detected, these power-consuming devices will automatically enter standby mode, which can greatly enhance the energy efficiency of IoT products and significantly extend the standby time of battery-powered products.
Compared to traditional presence detection methods like PIR (Passive Infrared), millimeter-wave radar’s high precision can detect static bodies, making it more accurate, especially when you are sitting still in front of the television. At the same time, millimeter-wave radar can penetrate non-metallic surfaces without needing to make openings, thus facilitating product appearance design.
To lower the threshold for using millimeter-wave radar, Infineon has adopted AiP (Antenna-in-Package) technology, supporting automatic working modes without hardware or software modifications, allowing engineers without expertise in RF, antennas, or radar signal processing to easily add millimeter-wave functionality to products.
Infineon and Aqara Green米 have launched
smart home solutions equipped with millimeter-wave radar
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Innovative Cooperation
The fourth type of innovation is in cooperation models. The birth of Infineon’s REAL3 3D ToF sensor is fundamentally different from other chip developments. This product was customized in deep collaboration with PMD Technology in 2013, based on PMD’s unique pixel matrix to develop a CMOS 3D image sensor. Infineon provides all functional components for the system-on-chip (SoC) integration. Additionally, both parties have collaborated to develop PMD ToF optimization CMOS manufacturing process standards. This deep cooperative innovation has led to a leap in ToF technology over the past decade.
Compared to radar technology, 3D ToF (Time of Flight) sensors are a newer technology. Radar determines objects by emitting and receiving electromagnetic waves, while 3D ToF projects a single modulated infrared light source onto the object, user, or scene of interest. The reflected light is captured by the ToF imager, which measures amplitude and phase differences pixel by pixel. The result is a highly reliable distance image along with a grayscale image of the entire scene.
It can be said that 3D ToF is the sensor that most resembles the human eye, capable of generating real-time three-dimensional images of objects, buildings, and humans. However, unlike traditional image sensors, ToF 3D sensors do not collect specific visual information, making them very suitable for applications with strict privacy requirements. They are also used in applications such as autofocus and SLAM. Compared to binocular ranging or structured light, ToF technology can directly obtain distance parameters.
Infineon’s ToF 3D image sensor has ultra-high precision and can even be used for facial recognition verification and payment scenarios. ToF cameras have been widely used in smartphones, and in 2021, Infineon announced collaboration with PMD and Huanrong to develop an all-in-one solution for under-screen ToF cameras in smartphones, enabling a new generation of smartphone designs without notches, four years ahead of the iPhone 12, which uses ToF technology.
PMD Technology is a ToF supplier with over 20 years of history, having accumulated 400 ToF technology patents. Based on PMD’s invention of the photonic mixer device (pmd), its sensors can simultaneously detect the intensity of light and distance values with high precision. Since launching its first ToF sensor in 2005, the product line has undergone ten generations of updates. Today, with Infineon’s REAL3 image sensor, PMD’s ToF technology has expanded from initial industrial imaging applications to a wide range of markets including automotive, robotics, smartphones, and AR.
In 2015, Infineon launched its first-generation REAL 3, and successfully applied its second-generation REAL 3 to Google Tango in 2016, four years ahead of the iPhone 12 using ToF technology. The collaboration between the two parties has become increasingly close, and by 2021, REAL 3 has successfully launched six generations of products.
The result of this deep cooperative innovation is that Infineon has delivered millions of 3D image sensors to date, and through the extensive commercial networks of both parties, has established partnerships with several module and system suppliers such as Sunny Optical, Huanrong, and others, making significant contributions to the popularization of ToF technology in various fields.
Andreas Urschitz, former president of Infineon’s Power and Sensor Systems Division (right), discusses the future of ToF with Bernd Buxbaum, CEO of PMD Technologies.
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Innovative Business Models
The fifth type of innovation is in business models. Traditionally, chip companies sell packaged chips that users can simply use. However, many also supply chips in bare die form, allowing customers to package them using their own technology. Infineon’s MEMS microphone business model operates this way.
Infineon has a unique positioning in the MEMS microphone supply chain, providing MEMS and ASIC chips to traditional ECM (Electret Condenser Microphone) manufacturers, such as well-known companies like Goertek, Knowles, BSE, and Partron. Infineon supplies semiconductor technology, while these partners have acoustic technology experience. Customers purchase Infineon’s MEMS wafers and sell them under their own brand. Although Infineon’s brand visibility is limited, this does not hinder Infineon’s success. Through this flexible business model, Infineon has rapidly become a leader in the MEMS microphone market.
With the development of IoT, voice has not only become a bridge for communication between people but also an important tool for human-computer interaction. Infineon launched its own brand of MEMS microphone packaged products in 2018 and collaborated with several auditory algorithm and system solution providers, such as Cloud Voice, SoundAI, and others, to apply MEMS microphones in smart interaction, noise reduction, voice enhancement, and even industrial operations.
Infineon’s partner Tempo’s TSDP1808x digital microphone aggregator (DMIC) and Infineon’s MEMS microphone work together to provide the industry’s highest performance multi-microphone solutions.
Innovative Applications
Today, with the leap in IoT technology, its applications are becoming diverse, providing Infineon sensors with more development space to continuously meet people’s innovative needs. For example, Toposens collaborated with Infineon in 2021 to utilize Infineon’s MEMS microphones and Toposens’ proprietary 3D ultrasonic technology to achieve 3D obstacle detection and avoidance capabilities for autonomous systems.
To quickly realize innovative applications, Infineon has been providing more possibilities in system innovation and software innovation.
Specifically, Infineon’s Sensor 2GO and Shield2Go evaluation boards help customers rapidly evaluate and prototype sensors. The Sensor 2GO evaluation board not only comes with sensors but also integrates Arm’s CPU, supporting onboard debugging. Moreover, various evaluation boards can plug and play with Arduino or Raspberry Pi, and support software library functions for rapid development. All interfaces are standard interfaces, allowing engineers to flexibly choose development boards according to their needs to customize complex system-level solutions.
For complex applications like radar, Infineon provides SDKs and basic algorithm libraries to lower the software development threshold for users.
Today, more and more startups are utilizing Infineon’s sensors to develop a rich variety of IoT applications, which undoubtedly demonstrates that Infineon’s strategy of lowering innovation thresholds has been successful.
Demonstration of a ping pong game using Infineon pressure sensor Shield2Go
Meanwhile, for practical applications, a single sensor is often insufficient to accurately describe a behavior, so multi-sensor fusion is no longer exclusive to automotive ADAS systems. More and more IoT markets are beginning to adopt sensor fusion technologies. Infineon’s multi-layer architecture alarm system reference is a typical IoT sensor fusion application, where data comes from MEMS microphones and pressure sensors. The microphone detects acoustic events, such as the sound of glass breaking, while the pressure sensor detects pressure changes, such as the indoor air pressure changes before and after glass breaks. The two types of hardware operate with different algorithms and are integrated through complex sensor fusion algorithms. The system will only alarm when both sensors are triggered simultaneously. This greatly enhances the robustness and reduces the false alarm rate of the glass breaking detection system. Additionally, the system can also detect intruders due to indoor pressure changes caused by opening doors or windows, further achieving intrusion detection.
Guoxin Liang, Chief Engineer of System Engineering at Infineon’s Power and Sensor Systems Division,
introducing Infineon’s glass breaking alarm system.
For example, Infineon collaborated with XMOS to combine Infineon’s radar and silicon microphone sensors with XMOS’s audio processor, achieving accurate far-field voice recognition through audio beamforming and radar target location detection.
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Innovation is Everywhere
To seek more comfortable, safer, time-saving, and user-friendly IoT devices, various innovations in human-computer interaction methods are emerging. As a key aspect of human-computer interaction, the sensor needs to provide a more intuitive and natural experience. At the same time, the types of sensors must also become more diverse to achieve optimized choices for different application scenarios. More importantly, with the development of edge AI technology, which can process more data, this also provides new development space for complex sensors that were previously unable to be applied to IoT.
In response to the current wave of sensors in the IoT, Infineon is accelerating innovation from various angles. This innovation is not only reflected in the products themselves, but also in Infineon’s application-oriented innovation strategy and innovative relationships with partners. to meet the fragmented and intelligent new patterns of IoT.
Further Reading: “Sensor Technology and Market Trends – 2020 Edition”, “Gas Sensor Technology and Market – 2022 Edition”, “Time of Flight (ToF) Sensor Technology and Applications – 2020 Edition”, “Automotive Radar Technology and Market – 2022 Edition”
