Analog Audio Noise Reduction

National's analog noise reduction solutions maintain excellent voice intelligibility with very low power consumption. Part of the PowerWise® family of energy-efficient solutions, National's noise suppression chips consume just 1/20th the power of comparable digital DSP and CPU software-based systems.

Microphone beamforming technology maintains voice clarity and intelligibility while canceling interference noise by dynamically adapting the system microphone pattern for wired accessories such as headphones and lanyards, mobile handsets, and smartphones. Active noise canceling technology reduces ambient noise by up to 25 dB over a wide frequency range for over-the-ear headphone designs and wired and Bluetooth® stereo headphones.

Using analog signal processing, National Semiconductor's adaptive beam forming technology extracts a clear, intelligible voice signal while providing up to 30 dB of peak noise rejection on both stationary and non-stationary noise sources. Its directional pattern dynamically adapts for optimum noise rejection based on the noise environment for wired accessories such as headphones and lanyards, mobile handsets, and smartphones. The beam forming engine uses signals from two microphones to adaptively change the microphone's polar pattern so that the dominant noise sources are suppressed and signal to noise ratio is continuously maximized.

• Latest News: National Semiconductor Acquires GTronix; Adds to Analog Audio and Voice Processing Capabilities for Wireless Handset Applications (press release)

Excellent Voice Intelligibility & Very Low Power

Uplink Solutions

Plug-and-play adaptive beamforming noise reduction microphone subsystems feature phase / sensitivity matched mics and programmable beamforming circuits that automatically reduce environmental noise for natural voice.

System Benefits

Up to 20 dB noise reduction Programmable null Very low power consumption Appears like a 2-wire or 3-wire mic to system Natural voice Wind noise alert and protection

Downlink Solutions

Active Noise Cancellation (ANC) enhances user experience by canceling ambient environmental noise. Products built on feedback architecture (over ear), feed-forward architecture (in ear), and hybrid architecture for optimum performance (-43dB).

System Benefits

Corrects for headphone variation Clearest voice and audio Very low power consumption Zero latency No custom software development Simplified design and manufacturing