原标题：Cirrus CS48LV12超低功耗HD音频处理方案

　　Cirrus公司的CS48LV12和CS48LV13是采用SoundClear®技术的超低功耗语音处理器,为高清(HD)语音质量性能,功能和成本效应提出了新标准,为智能手机,平板电脑,手持设备,扬声器/扬声器手机提供了完整的语音,音频播放和语音处理解决方案.本文介绍了CS48LV12/13主要特性,框图,CRD48L10-4in4out 评估板主要元件,输入/输出指标和框图.

　　The CS48LV12 and CS48LV13 ultralow power voice processors feature Cirrus Logic’s patented SoundClear® technologyto provide a new standard in HD Voice quality performance, functionality, and cost effectiveness. These ICs provide a totalvoice processing solution for handset and hands-free communications that deliver best-in-class noise reduction, echocancellation, and speech recognition. The CS48LV12 and CS48LV13 can enable advanced features including always-onvoice trigger, command recognition, ASR pre-processing, and audio enhancement. nnovative single and multi-mic algorithms with intelligent speech tracking and noice elimination assure optimal user experience in the most challengingand dynamic noise environments and deliver superior performance despite varying speech levels, talker distance, orproduct orientation.

　　The CS48LV12 and CS48LV13 feature an integrated media processor with built-in virtual surround, bass enhancement,bass synthesis, multi-band compression, and parametric EQ algorithms to enrich music playback through wirelessspeakers and headphones. All are tunable through a simple GUI. In addition, the CS48LV13 provides the option of addinga Cirrus Logic proprietary Voice Activity Detector for always-on ASR capability and integrated TrulyHandsfree™ VoiceControl. Also available is Cirrus Logic’s ASR Enhance™ specialized preprocessor to enhance the accuracy of any ASR(Automatic Speech Recognition) engine under noisy conditions. An expanded menu of third-party media playbackalgorithms from Dolby and DTS can also be integrated. Powerful real-time diagnostic and tuning tools combined withspecialized labs and a global applications support network assure ease of design, optimal performance, and achievementof network and industry compliance.

　　CS48LV12/13主要特性:

　　一般特性:

　　• Complete easy-to-implement voice solution including allessential voice, audio, and speech DSP features forflagship smartphones, tablets, and computing products

　　• SoundClear Voice™ noise reduction, echo cancellation,and voice enhancement

　　• RAPID2™ GUI-based diagnostic and tuning tool for easeof design-in

　　• Media postprocessing support

　　—Integrated Cirrus Logic playback enhancement forspeakers and headphones

　　—Optional Dolby® and DTS® playback enhancement

　　• ASR Enhance™ automatic speech recognition (ASR)preprocessing for increased ASR accuracy in noisyenvironments

　　• Voice activity detector (VAD) enables always-on speechrecognition

　　• TrulyHandsfree™ voice control by Sensory, Inc.supported

　　• Powerful 130-MHz dual-MAC 32-bit DSP core

　　• Ultralow power consumption (core typically <8 mW @ 1 Vduring narrowband call)

　　• I2S, I2C, SPI™ digital connectivity SoundClear Voice™ Features

　　• Flexible and tunable enabling freedom in product ID,transducer placement and selection

　　• Robust proprietary algorithms assure consistentperformance across diverse sound environments andoff-axis

　　• Ambient-aware technologies constantly compensate forchanging noise types and level and varying productpositioning

　　• HD voice/wideband and narrowband support

　　• Supports handset, tablet, laptop, and speakerphonesingle and multiple microphone configurations

　　• Conference room–grade AEC plus nonlinear residualecho suppressor for superior full-duplex speakerphoneoperation without echo

　　• Tx and Rx noise elimination

　　• Automatic volume control for both Tx and Rxcompensates variations in talker level, proximity, andorientation

　　• Ambient-aware volume control compensates for variationin Rx voice level and near-end noise level

　　• Tx and Rx comfort noise generators provide natural,smooth transitions between single-talk Rx, single-talk Tx,double-talk, and silent states

　　• Tx spectrally matched comfort-noise generator samplesand synthesizes ambient noise for more transparent talkstate transitions

　　• Tx and Rx parametric EQ simplifies carrier and industrycompliance,achieving natural sound and compensatingfor transducer limitations

　　—Up to four concurrent Tx and four concurrent Rx filters

　　—Eight different filter types can be combined to achieveexact requirements

　　—Each filter has tunable frequency, gain, and Q orbandwidth

　　• Ambient-aware dynamic parametric EQ for Tx or Rxenables automatic real time tuning for improvedintelligibility and to compensate for transducercharacteristics; responds to

　　—Tx or Rx stream amplitude

　　—Near-end ambient noise level

　　—User controls

　　• Rx compander for optimal speaker output level

　　• Mixed and mismatched microphone compensation

　　• Automatic calibration for up to ±6-dB sensitivity variation

　　• Compensation for microphone phase differences Cirrus Logic Speech Features(CS48LV13 Only)

　　• ASR Enhance preprocessor for ASR engines

　　—Improves speech command recognition of ASRengines in noisy environments

　　—Can be applied with VAD described below and optionalTrulyHandsfree voice control and/or cloud based ASR Optional Speech Features Supported(CS48LV13 Only)

　　• Sensory TrulyHandsfree voice control

　　• Complete always-on local ASR solution

　　—Ultralow power always-on Cirrus Logic voice detection(VAD)

　　—ASR Enhance pre-processor increases ASR accuracyin noisy conditions

　　—TrulyHandsFree voice trigger and voice command Audio Playback Features

　　• Full complement of Cirrus Logic audio-processingalgorithms preintegrated to enhance mono or stereoplayback over speakers or headphones

　　—Virtual surround

　　—Bass enhancement

　　—Bass virtualization

　　—Parametric EQ

　　—Multiband compressor

　　• Graphical interface for selection and tuning of algorithms

　　Optional Audio Playback Features Supported(CS48LV13 Only)

　　• Dolby® postprocessing (enhancement and virtualization)

　　• DTS® postprocessing (enhancement and virtualization)

　　• Headphone and speaker playback support

　　CS48LV12/13应用:

　　The CS48LV12/13 provides a complete voice, audioplayback and speech preprocessing solution forsmartphone, tablet, laptop, headphone/headset, andspeaker/speakerphone applications. They are optimizedfor devices where pristine voice quality and echo-free,full-duplex communication is required, especially underconditions of adverse noise and where space and powerare limited.

　　图1。CS48LV12框图

　　图2。CS48LV13框图

　　图3.CRD48L10-4in4out 评估板外形图

　　CRD48L10-4in4out 评估板主要元件:

　　• CS48L10 DSP

　　• CS42L73 Ultra Low-power CODEC

　　• CS35L01 Mono Class-D Amplifier

　　• CS8416 S/PDIF Rx

　　• CS8406 S/PDIF Tx

　　• Silicon Labs™ C8051F930 MCU

　　CRD48L10-4in4out 评估板输入/输出指标:

　　音频输入

　　1.1 Analog Line Input

　　• Connector Type: 1/8 inch (3.5mm) stereo Female

　　• Absolute Maximum Signal Level: +2.1 V

　　• Absolute Minimum Signal Level: –0.3 V

　　• Full Scale Amplitude (PGA VOL = 0 dB): 1.44 Vpp

　　• Reference Designators: J2 (LINE IN)

　　1.2 Analog Microphone Input

　　• Connector Type: 1/8 inch (3.5mm) stereo Female

　　• Absolute Maximum Signal Level: +2.1 V

　　• Absolute Minimum Signal Level: –0.3 V

　　• Full Scale Amplitude (PGA VOL = 0 dB/MIC PREAMP = +10 dB): 464 mVpp

　　• Full Scale Amplitude (PGA VOL = 0 dB/MIC PREAMP = +20 dB): 144 mVpp

　　• Reference Designators: J1 (MIC 1 & 2)

　　1.3 Optical Digital Input

　　• Connector Type: Fiber Optic Mini TOSLINK RX for Digital Audio

　　• Reference Designators: J4 (OPTICAL)

　　1.4 Coaxial Digital Input

　　• Connector Type: 1/8 inch (3.5mm) stereo Female

　　• Absolute Maximum Signal Level: +3.6 V

　　• Absolute Minimum Signal Level: –0.3 V

　　• Reference Designators: J4 (COAXIAL)

　　1.5 Digital Microphone Inputs

　　• Connector Type: 0.1 inch Male Header

　　• Absolute Maximum Signal Level: +2.1 V

　　• Absolute Minimum Signal Level: –0.3 V

　　• Reference Designators: J13 (DMIC)

　　1.6 I2S Digital Inputs

　　• Connector Type: 0.1 inch Male Header

　　• Absolute Maximum Signal Level: +6.5 V

　　• Absolute Minimum Signal Level: –0.5 V

　　• Reference Designators: TP3 (DSP), TP14 (VSP)

　　音频输出

　　2.1 Analog Line-level Outputs

　　• Connector Type: 1/8 inch (3.5mm) stereo Female

　　• Full Scale Output: 2.9 Vpp

　　• Reference Designators: J3 (LINE OUT)

　　2.2 Headphone Output

　　• Connector Type: 1/8 inch (3.5mm) stereo Female

　　• Full Scale Output: 1.5 Vpp

　　• Power: 2 x 17 mW (at THD+N = –60 dB)

　　• Minimum Load: 16 ohms

　　• Reference Designator: J5 (HEADPHONE)

　　2.3 Ear Speaker Output

　　• Connector Type: 100-MIL Male Header (2x1)

　　• Full Scale Differential Output: 2.3 Vpp (Digital Volume = –2.5 dB)

　　• Power: 0.51 W (at THD+N = –60 dB)

　　• Minimum Load: 16 ohms

　　• Reference Designator: J10 (EAR)

　　2.4 Speakerphone Left Output

　　• Connector Type: 100-MIL Male Header (2x1)

　　• Full Scale Differential Output: 5.8 Vpp (Digital Volume = –5.5 dB)

　　• Power: 0.53 W (at THD+N = –62 dB)

　　• Minimum Load: 8 ohms

　　• Reference Designator: J11 (SPKR-L)

　　2.5 Speakerphone Right Output

　　• Connector Type: 100-MIL Male Header (2x1)

　　• Full Scale Differential Output: 7.2 Vpp (Digital Volume = –3.5 dB)

　　• Power: 1.0 W (at THD+N = –74 dB)

　　• Minimum Load: 4 ohms

　　• Reference Designator: J12 (SPKR-R)

　　2.6 I2S Digital Output

　　• Connector Type: 100-MIL Male Header (6x2)

　　• Maximum Signal Level: +V_PROBE

　　• Reference Designators: TP3 (DSP), TP14 (VSP)