By St.J. Dixon-Warren and Rob Williamson, Chipworks, Inc. With
the new generation iPhone 3GS that was just announced, Apple is
trying to stay ahead of the pack for smartphones. The new
feature that captured our eyes is the electronic compass (also
called a magnetometer.) This is another example of a relatively
simple technology being elegantly applied with a sophisticated
software interface. One of the leaders in the magnetometer space
is MEMSIC, and while they did not win the iPhone socket (won by
the AKM AK8973), they are a forerunners to get design wins as
more electronics integrate this technology. The target device
discussed here is the Electronic Compass Board (ECB) evaluation
module from MEMSIC (figure 1), and it contains both their novel
thermal accelerometer and an electronic compass. Figure 1:
MEMSIC eval board The creation of a MEMS magnet is almost a
perfect example of elegant simplicity. Does anyone remember a
book called, “101 Things a Boy Can Make” by author Arthur C
Horth? Somewhere, in the mi