
REV. B
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a
AD1981B
Tel: 781/329-4700Fax: 781/326-8703
www.analog.comAC ’97 SoundMAX
Codec
FUNCTIONAL BLOCK DIAGRAM
A
M
MIC1
MIC2
PHONE_IN
CD_L
CD_GND
CD_R
AUX_L
AUX_R
LINE_IN_L
LINE_IN_R
MIC PREAMP
DIFCD
MONO_OUT
HP_OUT_L
HP
MZ
LINE_OUT_L
MZ
LINE_OUT_R
HP_OUT_R
HP
O
G = GAIN
- ADC
GA
- ADC
DAC RATE
M
- ADC
M
- ADC
PCM L/R
R
S
V
REF
G
V
REFOUT
CODEC CORE
DAC
SLOT
E
CAC '97
EAPD
PLL
XTL_OUT XTL_IN SPDIF
STX
ID0
ID1
RESET
SYNC
BIT_CLK
SDATA_OUT
SDATA_IN
JS0
JS1
EAPD
AD1981B
G
G
2
M
A
M
A
A
A
M
M
GA
M
GA
M
GA
M
GA
M
GA
M
GA
M
GA
M
GA
M
M
GA
M
M
B
EQ
B
EQ
G
G
RVOLTAGE
ANALOG MIXING
- DAC
- DAC
A
M
G
M
G
M
FEATURES
AC ’97 2.3 COMPATIBLE 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
Stereo Full-Duplex Codec
20-Bit PCM DAC
3 Analog Line-Level Stereo Inputs for
Line-In, AUX, and CD
Mono Line-Level Phone Input
Dual 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, Lead-Free Available
ENHANCED FEATURES
Stereo MIC Preamps Support
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
Software Programmed V
REFOUT
Output for Biasing
Microphone and External Power Amp
Split Power Supplies: 3.3 V Digital and 5 V Analog
Multiple Codec Configuration Options