Akustica develops two-chip analog MEMS microphone

March 29, 2012 // By R. Colin Johnson
Akustica is entering the mobile device market with its first analog microphone, a low-cost two-chip solution that it hopes will widen its market share.

The Bosch subsidiary pioneered the single-chip digital MEMS microphone back in 2006, when its biggest competition was analog mics designed for hearing aids.

Akustica is the world leader in digital MEMS microphones with its elegant one-chip CMOS solution that has captured the lion's share of the microphone market for digital devices like laptop computers. However, the larger mobile phone market has been slow to adopt digital microphones, opting instead to stick with the ultra-inexpensive analog microphones produced by high-volume manufacturers like Knowles Acoustics. Now Akustica, backed by Bosch's high-volume manufacturing capabilities, hopes to carve out a bigger share of the billion-unit mobile phone market.

Akustica's two-chip analog MEMS mic for cell phones and other mobile devices.

"Our first analog microphone meets the mobile phone requirements for features, form factor and power, and exceeds even the most stringent performance requirements," said Davin Yuknis, vice president of marketing at Akustica. "What’s more, because we are leveraging the Bosch supply chain--including their MEMS foundry in Germany--we are positioned to meet demand from even the highest-volume customers."

Akustica's AKU340 it its first analog microphone as well as its first to use a two-die solution--a MEMS diaphragm chip wire-bonded to an application-specific-integrated circuit (ASIC) housing the analog amplifier and interface circuitry (see photo) all in a tiny 2.5-by-3.35-by-1 millimeter package. Its small size and 63dB signal-to-noise ratio fit well with the requirements for mobile devices when used singly or in noise-canceling multi-mic arrays.

Akustica was acquired by Bosch in 2009 and will continue to market its unique single-chip digital MEMS microphones as well as the new lower priced analog MEMS mics.