REV. 0

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a

AD1981A

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.

Tel: 781/329-4700

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© Analog Devices, Inc., 2002

AC ‘97 SoundMAX

FUNCTIONAL BLOCK DIAGRAM

AC ’97 2.2-COMPLIANT CODEC

FEATURES

S/PDIF Output, 20 Bits Data Format, Supporting

48 kHz and 44.1 kHz Sample Rates

Integrated Stereo Headphone Amplifier

Variable Sample Rate Audio

External Audio Power-Down Control

Greater than 90 dB Dynamic Range

16-Bit Stereo Full-Duplex Codec

20-Bit DAC Input

Three Analog Line-Level Stereo Inputs for

LINE-IN, AUX, and CD

Mono Line-Level Phone Input

Mono MIC Input with Built-In Programmable Preamp

High Quality CD Input with Ground Sense

Mono Output for Speakerphone or Internal Speaker

Power Management Support

48-Lead LQFP Package

ENHANCED FEATURES

Built-in Digital Equalizer Function for Optimized

Speaker Sound

Full Duplex Variable Sample Rates from 7040 Hz to 48 kHz

with 1 Hz Resolution

Jack Sense Pins Provide Automatic Output Switching

Bias and External Power Amp

Split Power Supplies: 3.3 V Digital and 5 V Analog

Multiple Codec Configuration Options

SoundMAX is a registered trademark of Analog Devices, Inc.

EQ COEFF STORAGE

AC ’97 CONTROL REGISTERS

16-BIT

-

A/D

CONVERTER

16-BIT

-

A/D

CONVERTER

JACK SENSE

ANALOG

MUTE

CONTROL

LOGIC

MIC_IN

CD_L

CD_GND

CD_R

LINE_IN

HP_OUT_L

LINE_OUT_L

MONO_OUT

LINE_OUT_R

HP_OUT_R

AUX

PHONE_IN

HP

A

M

A

M

HP

A

M

MIC PREAMP

G

A

A

CD

DIFF AMP

M

GA

JS0

JS1

M

GA

M

GA

M

GA

M

GA

M

M

M

M

M

GA

M

GA

M

G

M

G

M

G

M

G

XTL_OUT

XTL_IN

ID1

ID0

XTAL OSCILLATOR

PLL CLOCK

GENERATOR

LINK PORT/

ID SELECT

A/D SAMPLE RATE

GENERATOR

20-BIT

-

D/A

CONVERTER

20-BIT

-

D/A

CONVERTER

16-BIT

-

A/D

CONVERTER

D/A SAMPLE RATE

GENERATOR

16-BIT

-

A/D

CONVERTER

SPDIF

SPDIF

AD1981A

EAPD

EAPD

SPKR

EQ

SPKR

EQ

VREF

G

M

GA

M

GA

M

GA

KEY:

G = GAIN

A = ATTENUATE

M = MUTE