The world's first gas sensor small enough for any smartphone was shown at the MEMS Executive Congress 2015 (held here, Nov. 4-6). Manufactured by Cambridge CMOS Sensors Ltd. (U.K.), the tiny 1 millimeter square MEMS-CMOS die are small and cheap enough to become ubiquitous — for the first time beating Apple in new types of MEMS sensors in smartphones.
Cambridge also announced its first design-win in K-Free Wireless Ltd. (Shenzhen, China). Carriers apply their own name to K-Free's white-box smartphones.
“We would love to be in Apple's iPhone, which the K-Free phone copies right down to the colors,” Jess Brown, a director at Cambridge told EE Times in an exclusive interview. “But we also have customers pending in the U.K. where sealed houses have the problem of dangerous gas build ups.”
Cambridge CMOS Sensors' design win at K-Free one-ups Apple with its new all-digital construction of a MEMS-CMOS CCS811 sensor. The sensor can be configured to sense volatile organic compounds (VOC) such as carbon monoxide from cheap heaters, formaldehyde in cheap furniture, or even used as a breathalyzer since driving-drunk is a jail-sentence offense in China, according to Brown.
In the U.K., a relatively new type of sealed house construction practice — putting plastic under the entire house, including the actual foundation — has opened a market for sensing noxious gas build-ups inside houses where there is no ongoing ventilation.
For other worldwide markets, the all-digital CCS811 sensor can be configured with different top-metal oxides or filters to detect only CO2, only ethanol, or nearly any other noxious gas. It can also be configured to measure the outside air quality, including nitrogen dioxide [NO2], in cities from Beijing to Los Angeles.
“It can tell you when to open window for ventilation while inside where very low levels of VOCs have been found to make people's minds 61 percent less efficient in decision making,” claimed Brown.
But the biggest benefit of the MEMS-CMOS gas sensor, according to Brown, is that it can be scaled continually as the International Technology Roadmap for Semiconductors (ITRS) scaled silicon chips to smaller and smaller sizes.
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