Thursday, July 12, 2012

#MEMS: "Six-axis MEMS sets new size/power low"

Smartphones and tablets today all have at least two MEMS chips in them--an accelerometer to switch screen orientation from portrait to landscape and a gyroscope to track motion for gaming and gesture recognition. The iPhone and iPad both use separate MEMS chips from STMicroelectronics for these functions, but Bosch Sensortec introduced a combo chip with both in the same package earlier this year. InvenSense, on the other hand, has had such a combo chip in production since 2010--they were probably just not chosen by Apple because they were still a privately owned startup. Since them Invensense has gone public, and now it has one-upped its rivals by downsizing the power consumption and the size of its latest six-axis combo accelerometer/gyroscope chip. No guarantee Apple will bite this time either, but many other smartphone and tablet makers have already chosen InvenSense and will welcome this smaller, lower-power combo MEMS: R. Colin Johnson

InvenSense's world's smallest lowest power six-axis MEMS combo chip combines a three-axis accelerometer with a three-axis gyroscope including on-chip sensor fusion using its digital motion processor.

Here is what EETimes says about Invensense: The latest six-axis MEMS combo chip combining a three-axis accelerometer and three-axis gyroscope from Invensense Inc. (Sunnyvale, Calif.) sets a new low in size and power.

In 2010 Invensense announced the world's first six-axis accelerometer/gyroscope combo chip—the MPU-6000—which measured 4-by-4 millimeters, but earlier this year Bosch Sensortec announced a six-axis combo chip that measured 3-by-4.5 millimeter (16 percent smaller than MPU-6000). Also last year, STMicroelectronics—supplier of accelerometers and gyroscopes for Apple's iPad and iPhone announced a six-axis combo chip but it measured 4-by-5 millimeter (25 percent bigger than MPU-6000). Invensense's latest six-axis combo chip now sets a new low, making it the undisputed smallest-size award winner by measuring just 3-by-3 millimeters. Invensense also lays claim to the lowest power consumption, by virtue of eliminating the need for a three-volt power supply to its MEMS devices, there by running the whole chip off a power saving 1.8 volts.

InvenSense uses a proprietary process that wafer bonds its ASIC holding CMOS circuitry to the MEMS wafer holding the mechanical parts before dicing, enabling the industry's only true single-chip combo.

Invensene also claims that by boosting the performance of its MEMS elements, which are wafer bonded to the ASIC holding the DMP and other CMOS circuitry using a proprietary process (see figure above), it is targeting next-generation high-performance location-based services, such as pedestrian navigation and context-aware advertising.
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