http://www.pnicorp.com/blog/stmicroelectronics-and-pni-sensors-selected-nintendo%E2%80%99s-wii-u-12192012 said:
"We are pleased to have Nintendo, a true pioneer in interactive entertainment, select our geomagnetic sensor for use in the Wii U. And working closely with ST has made this possible" said Becky Oh, PNI Sensor President and CEO. Our goals are to offer our sensors to customers who need to sense motion despite some magnetic interference, to complement their algorithms, and to react in real time."
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Designed and manufactured in Northern California, the PNI RM3000 geomagnetic sensor enables motion sensing while also accounting for reasonable magnetic anomalies. It detects magnetic fields in the environment with improved accuracy, even where magnetic interference from audio speakers, metal objects, building girders or a cell phone can send other magnetic sensors off target. STs ASIC amplifies signals, from a tiny variation of magnetic field detected by magnetic sensor coils, and with low noise, converts them to digital data, and interfaces with an application processor through an SPI bus.
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