TI LMV1051

LMV1051
LMV1051 PRODUCT BRIEF Processor for Dual Microphone Adaptive Noise
Cancelling with Wind Noise Alert
Literature Number: SNAS508
September 21, 2010
Processor for Dual Microphone Adaptive Noise Cancelling
with Wind Noise Alert
General Description
Features
The LMV1051-LLP is an ultra-low power signal processor that
processes the signals from 2 ECM or MEMS microphones to
create an adaptive beam forming noise reduction system.
The LMV1051-LLP processor is intended to be integrated
with microphones (ECMs or MEMS). By using a proprietary
National algorithm, the processor extracts a clean intelligible
signal from noisy environments through the use of an adaptive directional pattern. The resulting solution can reduce
noise by up to 30 dB, resulting in a significant improvement
to the signal-to-noise ratio (SNR). The signal processing does
not introduce artifacts into the talker’s voice. The desired signal is unmodified, which improves intelligibility and speech
recognition accuracy.
The LMV1051-LLP is designed to replace a standard ECM
using a two-wire or three-wire interface. The entire module,
including the processing IC, is powered from the mic bias
supply. The resulting system uses less power than an individual ECM giving the end-product designer the ability to
upgrade current designs without modifying the existing circuit.
The result is an easy-to-use, low cost microphone alternative,
providing superior noise reduction for end users.
Notice: This document is not a full datasheet. For more
information regarding this product or to order samples
please contact your local National Semiconductor sales
office or visit http://www.national.com/support/dir.html
■ Superior Noise Cancellation
■
■
■
■
■
■
■
■
■
— Dual Mic Technology
— Active Directional Pattern
— Up to 30dB peak noise rejection of stationary and nonstationary noise sources
— No distortion of desired signal
— Flat Frequency Response
Wind Noise Alert and Protection
— Automatically reduces wind noise by ≈ 20 dB (vs.
directional mic)
— Wind Noise Alert can be used to further reduce impact
of wind on desired signal
Ultra-Low Power Consumption
— 210 μA (typical) including mic bias
— Battery-free operation in wired headsets
Compatible with Standard ECM Interfaces
— 2-wire or 3-wire interface
— Powered from mic bias supply
Complete Signal Processing Solution
— No Software Required
— Enables a fully integrated mic module
Zero-Latency Signal Processing
Noise Cancelling or Omni-Directional Output
Better EMI Noise rejection than ECM
Supports Telephony Bandwidth
Small Size 3 x 3 mm
Applications
■ Wired Headset
■ Webcams
■ Cellular or Cordless Handsets
© 2010 National Semiconductor Corporation
301336
www.national.com
LMV1051 PRODUCT BRIEF
LMV1051
PRODUCT BRIEF
LMV1051
Block Diagram
30133601
Typical Applications Circuit
30133602
www.national.com
2
LMV1051
Notes
3
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LMV1051 PRODUCT BRIEF
Notes
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