Norwood, Mass. Analog Devices, Inc. (ADI) has developed a new family of digital and analog micro-electromechanical systems (MEMS) microphones that claims the industry's best signal-to-noise ratio (SNR) and frequency response. These devices are capable of high-fidelity audio/video playback, conference calling, TIA-920-compliant VoIP (voice-over-IP), voice recognition, and other functions.
Touting the industry's highest SNR of greater than 61-dB A-weighted, the new omni-directional input microphones are available with digital output (ADMP421) or analog output (ADMP401) and are said to deliver the industry's flattest frequency response from 100 Hz to greater than 15 kHz. ADI also says the devices come in a package size and cost tailored to the design considerations of portable electronics manufacturers.
The ADMP421 PDM (pulse density modulated) digital output MEMS microphone is designed for multimedia and VoIP-enabled cell phones, Bluetooth headsets and other systems that rely on high quality digitized voice and audio. The digital output provides high immunity to coupled noise from radio frequency (RF) and electromagnetic interference (EMI) emanating from sources such as WiFi antennas and LCD clock signals.
By eliminating the need for analog signal conditioning, as well as the cable shielding materials commonly required to route analog signals, system designers can optimize the placement of the ADMP421 MEMS microphone to improve audio-enhancement features such as stereo sound and array beam forming. The device features better than +80 dB FS power supply rejection ratio (PSRR), Left/Right select, and integrated sleep mode.
In addition to providing the industry's best SNR and frequency response, the ADMP401 analog output MEMS microphone delivers a PSRR of better than +50 dB, simplifying power supply design requirements to the microphone for near-field and far-field applications.
Pricing: The ADMP401 is priced at $1.63 and the ADMP421 at $2.04, in quantities of 1,000.
Availability: The ADMP401 analog-output MEMS microphone is sampling now in a 4.72 x 3.76 x 1.0-mm surface-mount package, and the ADMP421 digital-output MEMS microphone is sampling now in a 4.0 x 3.0 x 1.0-mm surface-mount package.
Product information: MEMS microphones, ADMP401, ADMP421, and iMEMS technology
Analog Devices , www.analog.com