The layout of the acceleration sensor manufactured by Kionix
The layout of the acceleration sensor manufactured by Kionix
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Sensor manufacturers have been in keen competition over the three-axis acceleration sensor used in the controller of Nintendo Co Ltd's "Wii" game console.

The acceleration sensors are currently supplied by Analog Devices Inc (ADI) of the US and Franco-Italian firm STMicroelectronics (ST). But other manufacturers have been courting Nintendo with the aim of becoming a new supplier.

Nintendo has been evaluating samples obtained from a number of acceleration sensor manufacturers other than ST and ADI, according to sources. Kionix Inc, a US-based venture firm, once attracted attention as a strong candidate.

Kionix was regarded as such because of the high reliability based on its past records of supplying sensors for hard disk devices, according to a source involved in the case. Also, Kionix's device has a structure different from its competitors: Its MEMS sensor is several times thicker than ADI's device, making it "easier to enhance sensitivity," according to engineers in the MEMS industry.

Nevertheless, Nintendo has not yet decided to change suppliers. Acceleration sensor manufacturers have to satisfy strict specification requirements in order to obtain a contract.

"It is difficult for manufacturers to be selected as a new supplier," said an employee at an acceleration sensor manufacturer.

The battle over this attractive position seems to continue for some time to come.