getbigsoundfromsmallspeakerswithwolfson’sinnovative retune ... · 2-19-12 takashima nishi-ku...

Portable navigation systems

Mobile handsets

Speaker phone systems

Multimedia accessories

Digital radios

tarGet applications product benefits

High performance audio, delivers optimumsound pressure levels (SPL), from low costspeaker applications

Programmable dynamic range controlboosts low-level signals to maximisevolume for improved intelligibility

ReTune™ Mobile Parametric Equaliserenables end user defined music profiles

Signal limiter to prevent speaker damagefrom signal clipping and distortion

Integrated register write sequencer tominimise software development time

WM9081

The WM9081 is a mono DAC with an integrated,high efficiency, switchable Class AB/D speakeramplifier, capable of delivering up to 2.6W into a4Ω load. It is ideal for providing optimum soundpressure levels (SPL) from low cost speakers inapplications such as portable navigation devices.Compared to a commonly used fab chip solutionof DAC and Class D amplifier, WM9081consumes 30% less PCB area and achieves20% BOM reduction.

Additionally, the combination of package size,digital audio interface and integrated speakeramplifier in WM9081 give the system designerseveral advantages in terms of noise reduction.The I2S audio interface removes the need toroute noise susceptible analog audio signalsacross a potentially noisy PCB. The WM9081 canbe placed very close to the speaker connectors,minimising the Class D track lengths whichcarry noisy high frequency switching currents.

Mono dac with integrated 2.6W class ab/d speaker amplifier

Get biG sound froM sMall speakers With Wolfson’s innovativeretune™ Mobile paraMetric equaliser.

LINEOUT

SPKOUTP

SPKOUTN

AVDD

VMIDC

AGND

SPKGNDSPKVDDDCVDDDGNDDBVDD

0dB / -6dB+6dB to -57dB

1dB STEPS

+6dB to -57dB1dB STEPS

SPEAKER BOOST+5.1dB to 0dB

VOLTAGEREFERENCE

0dB / -6dB

WM9081

IN1

IN2

CS / ADDR1 / 4FS

SCLK

SDIN / ENA

SDOUT / ADDR0

SCIM / CHANNEL

SWMODE

CONTROLINTERFACE

FLL

DAC

MIXER

DIGITAL FILTERS

VOLUME CONTROL

PARAMETRIC EQ

DYNAMIC RANGECONTROLLER

DIGITAL AUDIOINTERFACE

CLOCK CONTROL

IRQ

DACDAT

BCLK

LRCLK

MCLK

WM9081

Mono DACwith integrated2.6W Class AB/Dspeaker amplifier

WM9081

Mono dac with integrated 2.6W class ab/d speaker amplifier

For more information please visitwww.wolfsonmicro.com

or sign up for Wolfson eNews at:www.wolfsonmicro.com/enews

World headquarters

Wolfson Microelectronics plc

Westfield House26 Westfield RoadEdinburghEH11 2QBUnited Kingdom

t: +44 (0)131 272 7000f: +44 (0)131 272 7001e: [email protected]

usa sales office

Wolfson Microelectronics, inc.

10001 N. De Anza BoulevardSuite 301CupertinoCA 95014USA

t: +1 (408) 329 9800e: [email protected]

Japan sales office


23F Sky Building2-19-12 TakashimaNishi-kuYokohama, 220-0011Japan


asia pacific sales office


2F, No.39, Alley 20Lane 407, Sec. 2Tiding Boulevard, NeiHu DistrictTaipei 114Taiwan


© copYriGht 2009, Wolfson Microelectronics plc. and the wave logo are a registered trademark of Wolfson Microelectronics plc. all other trademarked names, whether indicated as such or not, are the property of their respectiveowners. the information in this document is believed to be accurate in all respects at the time of publication but is subject to change without notice. Wolfson Microelectronics plc assumes no responsibility for errors and omissions, and disclaims responsibilityfor any consequences resulting from the use of information contained in the document.

product features

Mono I2S 24bit DAC with integrated mono2.6W Class AB/D speaker amp

Exceptional audio performance92dB SNR, 1% THD @ 2.4W

Fully parametric 5 band equaliser

Output limiter and dynamic rangecontroller

Auxiliary analogue inputs and mono lineoutput

Integrated FLL for flexible clocking,supports 8kHz – 27MHz range

75dB PSRR @ 217Hz on SPKVDD foroptimal noise rejection

Sample rates 8kHz – 96kHz

2/3 wire software control and hardwarecontrol modes

eXceptional audio perforMance

WM9081 provides Wolfson’s brand renownedhigh performance audio, with 92dB SNR inClass D mode and 1% THD+N @ 2.4W outputpower levels into 4Ω speaker loads, so designersof portable systems do not need to sacrifice onaudio performance when seeking maximumoutput power.

diGitallY optiMised sYsteMperforMance

The WM9081 integrates a five-band ReTune™Mobile Parametric Equaliser with fullyprogrammable coefficients for optimisation ofspeaker characteristics and speaker frequencyresponse compensation, allowing the end userto define music profiles. Programmabledynamic range control is integrated to helpboost low-level signals to maximise volumefor improved intelligibility. The WM9081 alsofeatures a dynamic range controller (DRC) andlimiter. The limiter prevents the audio signalfrom clipping and causing audible distortion,overloading the battery and potentiallydamaging the speakers. Whilst the DRCautomatically boosts low level signals tomaximize volume for improved intelligibility.

inteGrated reGister Writesequencer

Software development time can be minimisedthrough the use of an integrated register writesequencer. A number of signal paths (such asDAC to speaker mode) can be easily enabledand disabled by just one register write. Theinternal sequencer manages this by initiatinga sequence of pre-programmed multiple writesindependently within the WM9081, minimisingcontrol interface communication between theprocessor and WM9081.

Wisce™ developMent environMentand evaluation tools

For engineers who want to configure all theoptions on WM9081, a full evaluation systemis available. This includes an evaluation boardand full schematics, Linux driver and WISCE™(Wolfson Interactive Set-up ConfigurationEnvironment). WISCE™ is a downloadablesoftware GUI, which allows the developer tomake real time modifications to an interactiveversion of the register map and modify thedevice configuration, whilst developingsoftware settings.

0 2.50.5 1 1.5 2

OUTPUT POWER (W)

5

2

1

0.5

0.2

0.1

0.05

0.02

0.01

0.005

TH

D+

N(%

)

eXceptional thd+n perforMancespk thd+n ratio vs pout 4Ω

• SPKVDD = 5.0V, AVDD = 3.3V, DCGAIN / ACGAIN = 3.6dB



• SPKVDD = 3.3V, AVDD = 3.3V, DCGAIN / ACGAIN = 0dB

CONTACT DETAILS www.wolfsonmicro.com

PO

-FL-

9081

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09

getbigsoundfromsmallspeakerswithwolfson’sinnovative retune ... · 2-19-12 takashima nishi-ku...

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