Wolfson公司的WM2200是低功耗具有增強的Wolfson myZoneTM環境噪音消除（ANC）的CODEC，為近端和遠端用戶提供了增強的語音質量。WM2200可以直接驅動耳機放大器，包括myZoneTM接收和發送通路的噪音消除和回聲消除（AEC）算法，提供風噪音，電話機側音和其它可編程的濾波器，多達6個模擬或數字麥克風，單端或差分模擬麥克風輸入，AB類或W模式工作，主要用在移動手機。本文介紹了WM2200主要特性，方框圖以及手持機模式和揚聲器模式應用框圖。
Low Power CODEC with Enhanced Wolfson myZoneTM Ambient Noise Cancellation
The WM2200 is a low power mobile CODEC with enhanced Wolfson myZoneTM Ambient Noise Cancellation (ANC). It provides enhanced voice communication quality for both near and far end handset users.
WM2200 drives the receiver earpiece speaker directly, includes myZoneTM receive path (RX) and transmit path (TX) Noise Cancellation and Acoustic Echo Cancellation (AEC) algorithms, and can be used in speakerphone mode using a PDM input speaker amplifier chip.
The device can be used for both narrowband and wideband voice calls and can be coupled with analogue and digital microphones. Baseband processors with analogue or digital voice RX and TX signals are supported.
The Wolfson myZoneTM (ANC) engine uses two or three analogue or digital microphones, allowing the enhanced filtering algorithm to consistently deliver the optimum noise cancellation performance.
The TX Noise Cancellation and Acoustic Echo Cancellation algorithms require one or two analogue or digital microphones.
The device is supplied via a single external 1.8V supply and requires an external clock (MCLK). It can be programmed via 2-wire serial control interface
WM2200主要特性：
Programmable audio effects and voice-processing functions
−myZoneTM adaptive ambient noise-cancellation for earpiece
−Transmit-path noise-cancellation and echocancellation
−Wind noise, side-tone and other programmable filters
Audio inputs
−Up to 6 analogue or digital microphones
−Single-ended or differential analogue microphone input
−1 single-ended or differential line input
Earpiece drivers
−Differential (BTL) drive configuration
−Class AB or W mode of operation
−-80dB THD at 20mW into 32Ω load
−DAC to earpiece SNR, AB mode (A-weighted)
>= 97dB
−Pop-click minimization
GPIO
DAC to ADC crosstalk better than 100dB
PDM digital output for speakerphone support
Digital Audio for digital RX and TX voice
Hearing Aid Coil
90-ball W-CSP package
WM2200應用：
Mobile telephony
圖1。WM2200方框圖
圖2。WM2200手持機模式應用框圖
圖3。WM2200揚聲器模式應用框圖
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