STMicroelectronics (NYSE: STM),
the leading supplier of MEMS for consumer and portable applications(1), has
integrated a 3-axis digital accelerometer with a 3-axis digital magnetic sensor
in a single module.
The digital compass module combines high accuracy with small form factor and
low power consumption at a competitive cost, meeting the growing market demand
for advanced navigation capabilities and emerging smart location-based services.
ST's high-performance system-in-package digital compass uses magneto-resistive
technology from Honeywell and aims to accelerate the adoption of enhanced electronic
compassing in portable consumer applications, including direction finding, map/display
orientation, location-based services and pedestrian dead reckoning.
The combination of high-performance motion and magnetic sensing enhances the
mobile-user experience in a number of ways. ST's new module adds forward direction
orientation that enables application developers to improve the use of limited
phone/PDA display size for maps by putting the current user position at the
bottom of the map with the rest of the display in the forward ('up ahead') direction.
ST's digital compass provides accurate heading information, to indicate the
direction in which a person or vehicle is moving, when GPS is not available.
It also supports dead-reckoning applications, including pedestrian navigation
in places with no or low GPS signal, such as inside buildings and structures
or in mountainous and forested terrain.
Compass modules in handsets open new possibilities for advanced location-based
services. With compassing and GPS capabilities, consumers will be able to identify
and retrieve information on nearby points of interest, such as restaurants or
shops, by simply pointing their mobile devices in the direction of the object
"As the one-stop MEMS supplier of choice, STMicroelectronics is paving
the way to smart sensor modules," said Benedetto Vigna, Group Vice President
and General Manager of the MEMS, Sensors and High Performance Analog Division,
STMicroelectronics. "We have accelerometers, gyroscopes, microphones and
now, thanks to our cooperation with Honeywell, also magnetic sensors. We are
ushering in an era of integrated sensing capabilities."
The new module leverages ST's market-proven manufacturing technology and robust
design that ST has already successfully applied to more than 600 million accelerometers
sold into the market. High-precision sensing couples with smart embedded features,
including wake-up/power-down function and 6D recognition, which signals if the
device is up or down along all three axes (x,y,z). The device has a linear acceleration
full-scale of plus or minus 2/plus or minus 4/plus or minus 8g and a magnetic
field full-scale from plus or minus 1.3 up to plus or minus 8 gauss(2), both
fully selectable by the user.
The magnetic sensing element that measures the strength and direction of the
Earth's magnetic field and determines the heading relative to magnetic north
is based on Honeywell's Anisotropic Magneto-Resistive (AMR) technology. This
technology combines best-in-class accuracy in compass calculations with low
power consumption, which is crucial in battery-hungry portable devices.
The AMR technology provides the same sensitivity on the z axis as it does on
the x and y axes, eliminating the need for flux concentrators used in Hall-effect
type sensors that can shift the sensor offset after it has been magnetized.
This market-unique three-axis sensing approach reduces measurement errors in
ultra-low magnetic field strength environments, such as in metal buildings,
automobiles, or in higher latitudes like Canada or Northern Europe.
Moreover, Honeywell's magnetic sensor design includes a built-in offset cancellation
circuit to minimize the need for calibration, and patented set/reset straps
that de-gauss, or de-magnetize, the sensor for each measurement to improve accuracy.
According to iSuppli, the market for MEMS digital compasses for use in mobile
phone applications alone will grow from 8 million units in 2008 to 540 million
units in 2013 - a CAGR of 129%. During the same time period, revenues for these
components will grow at a CAGR of 110%, from $8 million to $325 million.
ST's LSM303DLH digital compass module fits in an eco-friendly package of 5x5x1
mm and it is software- and register-compatible with ST's three-axis digital
accelerometer family (LIS331DLH/M/F). Samples are available and the device is
ready for mass production. Unit pricing is $2.5 for volumes in the range of