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The second MBSS approach is called commoditized integration. Here, standard off-the-shelf MEMS devices are used in conjunction with ASICs and DSP with proprietary application software and packaging to create a solution. Examples of this approach are being demonstrated by Schrader Electronics in its tire pressure monitoring systems. These use standard off-the-shelf pressure and motion sensors.
Hillcrest Laboratories and Movea, in their human-machine interface device for gesture recognition products, employ MEMS accelerometers and gyros. The value added to these commoditized solutions is the knowledge of the application and the ability to successfully accomplish intelligent systems integration and provide software programming specific to the application. All of this is neatly packaged in a low-cost device.
Drivers for MBSS adoption
There are a number of drivers, both technical and business, that will make MBSS adoption a major business success for MEMS. The most significant of these are cost, availability, market expansion, and the need for product differentiation and optimization of gross margin on the part of the solution supplier. A downward price spiral that has occurred over the past 15 years when $5 (high-volume) devices were introduced. ADI's ADXL 50 one-axis accelerometer for automotive airbag applications displaced electromechanical systems costing three times as much.
Now, a three-axis accelerometer can be had for less than $0.75 (in large volumes) from a number of suppliers including Bosch, Kionix, and STMicroelectronics. MEMS gyros are following the same path but are still selling in the low single digits for large volumes. Invensense is leading the charge in this area.
Pressure sensors have also seen significant price declines. This maturing or commoditization has enabled large-volume applications including mobile phones and games to adopt these low-cost devices as integral to their strategy of providing many more functions and higher performance and efficiency. This helps create product differentiation between phone suppliers. In addition, the necessity of the MEMS device to work in conjunction with a signal processor in the form of a commercially available ASIC and/or DSP from many vendors including e2V, SiWare Systems, Austria Microsystems, Triad Semiconductor, and Microchip provides solution designers with a wide choice of partners. As one can see, the barriers to entering the MBSS market from a commoditized approach can be lower than that of the enabling engine approach.
However, the enabling engine approach has a number of companies actively pursuing application opportunities. This includes Polychromix, who has created a hand-held optical spectrometer, and C2V (which has recently been acquired by Thermo Fisher) who has created a MEMS microfluidic gas chromatograph. Research shows that portable analytical instruments hold great promise to propel MEMS-based spectrometers and chromatographs into the laboratory diagnostics and medical point of care application sectors.
One of the other major adoption drivers of MBSS is the quickly developing MEMS packaging and testing area. Ten years ago, MEMS packaging was an afterthought. Today, it's a product differentiator and an area of great development. Because MEMS packaging and cost typically represent over 50% of the bill of materials, MEMS suppliers, especially those of price-sensitive consumer devices, have introduced low-cost packaging and test strategies. Hence, the infrastructure to support the development of MBSS is alive and well and ready to support the development of a broad range of future MBSS implementations.
Although MBSS has been around for many years, the proliferation of this approach is being fueled by the availability of low-cost MEMS devices and signal conditioning ASICs and DSP, as well as packaging and high-throughput testing. The need for gesture recognition in games, toys, computer peripherals (mice), medical, sports, and fitness bodes well for this approach. In addition, as the need to better understand the quality of food and water as well as the chemical and biological composition of many substances to enhance society’s quality of life, MBSS for spectrometers and chromatographs for handheld instruments will fuel the enabling engine concept.
About the author
Roger H. Grace, an expert in the MEMS field, is the President of Roger Grace Associates. He can be reached at firstname.lastname@example.org.