Bosch Sensortec has newly fabricated a tiny 700 square micron digital microphone, the world's smallest MEMS chip for its subsidiary Akustica.
The CMOS die combines a mechanical microphone diaphragm with a mixed signal CMOS circuitry, which terminates in a typical PDM (Pulse Density Modulation) output.
Using Bosch's CMOS process, Akustica has shrunk the size of its die by 80 percent, yielding five-times as many chips per wafer.
According to IHS iSuppli, in 2010, MEMS microphone has topped 695 million units in the market, which is more than 57% comparing to 2009. It is expected, that delivery will increase above 1.7 billion units or $471 million in 2014. The Microphone applications include mobiles, touchscreen tablets, PCs, laptops, netbooks, Bluetooth headsets and camera modules.
The chip designers are capable of compressing the die's area by another 30%, which is previously reduced from two- to one-mm2 and produces a new digital microphone with the world's smallest MEMS die at 700 square microns.
This die size reduction is possible only because of Bosch's experience in decreasing high-performance circuitry and it also maintains low noise and enhances sensitivity. This microphone is very thin so that it can be fixed into bezels of any PC, laptop, netbook for directionality and noise cancellation.
The plan of Akustica is to further economize the present 3.8-by-4.7-by-1.3 mm package for handheld devices to fit hi-fi MEMS microphones into ultra-thin mobile phones.
Source: http://www.bosch-sensortec.com/