AC’97 FEATURES
Fully Compliant AC’97 Analog I/O Component
48-Terminal LQFP Package
Multibit ⌺⌬ Converter Architecture for Improved
S/N Ratio >90 dB
16-Bit Stereo Full-Duplex Codec
Four Analog Line-Level Stereo Inputs for Connection
from LINE, CD, VIDEO, and AUX
Two Analog Line-Level Mono Inputs for Speakerphone
and PC BEEP
Mono MIC Input Switchable from Two External
Sources
High Quality CD Input with Ground Sense
Stereo Line Level Output
Mono Output for Speakerphone
Power Management Support
FUNCTIONAL BLOCK DIAGRAM
AD1819B
MIC1
MIC2
LINE_IN
AUX
CD
VIDEO
PHONE_IN
LINE_OUT_L
MONO_OUT
LINE_OUT_R
PC_BEEP
0dB/
20dB
MV
MV
MV
G
A
S
M
PHAT
S
S
STEREO
S
S
A
M
PHAT
S
STEREO
ENHANCED FEATURES
Support for Multiple Codec Communications
DSP 16-Bit Serial Port Format
Variable 7 kHz to 48 kHz Sampling Rate with 1 Hz
Supports Modem Sample Rates and Filtering
Phat™ Stereo 3D Stereo Enhancement
VHDL and Verilog Models of Serial Port Available
G
G
A
M
SS
SSSS
G = GAIN
A = ATTENUATE
M = MUTE
MV = MASTER VOLUME
G
A
M
G
A
A
M
M
S
S
S
Resolution
G
A
M
S
S
PGA
SELECTOR
PGA
G
A
M
G
A
M
CS1
CS0
MASTER/SLAVE
SYNCHRONIZER
16-BIT
SD A/D
CONVERTER
16-BIT
SD A/D
CONVERTER
SAMPLE
RATE
GENERATORS
16-BIT
SD D/A
CONVERTER
16-BIT
SD D/A
CONVERTER
OSCILLATORS
XTALO
CHAIN_IN
XTALI
CHAIN_CLK
RESET
SYNC
BIT_CLK
AC LINK
SDATA_OUT
SDATA_IN
SoundPort is a registered trademark of Analog Devices, Inc.
Phat is a trademark of Analog Devices, Inc.
REV. 0
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
The AD1819B is an analog front end for high performance PC
audio, modem, or DSP applications. The AC’97 architecture
defines a 2-chip audio solution comprising a digital audio controller, plus a high quality analog component that includes
Digital-to-Analog Converters (DACs), Analog-to-Digital Converters (ADCs) mixer and I/O.
The main architectural features of the AD1819B are the high
quality analog mixer section, two channels of Σ∆ ADC conversion, two channels of Σ∆ DAC conversion and Data Direct
Scrambling (D
2
S) rate generators. The AD1819B’s left channel
ADC and DAC are compatible for modem applications supporting irrational sample rates and modem filtering requirements.
FUNCTIONAL DESCRIPTION
This section overviews the functionality of the AD1819B and is
intended as a general introduction to the capabilities of the
device. Detailed reference information may be found in the
descriptions of the Indexed Control Registers.
Analog Inputs
The codec contains a stereo pair of Σ∆ ADCs. Inputs to the
ADC may be selected from the following analog signals: telephony (PHONE_IN), mono microphone (MIC1 or MIC2),
stereo line (LINE_IN), auxiliary line input (AUX), stereo CD
ROM (CD), stereo audio from a video source (VIDEO) and
post-mixed stereo or mono line output (LINE_OUT).
Analog Mixing
PHONE_IN, MIC1 or MIC2, LINE_IN, AUX, CD and
VIDEO can be mixed in the analog domain with the stereo
output from the DACs. Each channel of the stereo analog inputs may be independently gained or attenuated from +12 dB
to –34.5 dB in 1.5 dB steps. The summing path for the mono
inputs (PHONE_IN, MIC1, and MIC2 to LINE_OUT) duplicates mono channel data on both the left and right LINE_OUT.
Additionally, the PC attention signal (PC_BEEP) may be
mixed with the line output. A switch allows the output of the
DACs to bypass the Phat Stereo 3D enhancement.
Analog-to-Digital Signal Path
The selector sends left and right channel signals to the programmable gain amplifier (PGA). The PGA following the selector
allows independent gain for each channel entering the ADC
from 0 dB to +22.5 dB in 1.5 dB steps.
Each channel of the ADC is independent, and can process
left and right channel data at different sample rates. All programmed sample rates from 7 kHz to 48 kHz have a resolution
of 1 Hz. The AD1819B also supports irrational V.34 sample
rates.
Sample Rates and D2S
The AD1819B default mode sets the codec to operate at 48 kHz
sample rates. The converter pairs may process left and right
channel data at different sample rates. The AD1819B sample
rate generator allows the codec to instantaneously change and
process sample rates from 7 kHz to 48 kHz with a resolution of
1 Hz. The in-band integrated noise and distortion artifacts introduced by rate conversions are below –90 dB. The AD1819B
uses a 4-bit D/A structure and Data Directed Scrambling (D
2
S)
to enhance noise immunity on motherboards and in PC enclosures, and to suppress idle tones below the device’s quantization
noise floor. The D
2
S process pushes noise and distortion artifacts caused by errors in the multibit D/A conversion process to
frequencies beyond the audible range of the human ear and then
filters them.
Digital-to-Analog Signal Path
The analog output of the DAC may be gained or attenuated
from +12 dB to –34.5 dB in 1.5 dB steps, and summed with any
of the analog input signals. The summed analog signal enters
the Master Volume stage where each channel of the mixer output may be attenuated from 0 dB to –46.5 dB in 1.5 dB steps or
muted.
Host-Based Echo Cancellation Support
The AD1819B supports time correlated I/O data format by
presenting mic data on the left channel of the ADC and the
mono summation of left and right output on the right channel.
The ADC is splittable; left and right ADC data can be sampled
at different rates.
Telephony Modem Support
The AD1819B contains a V.34-capable analog front end for
supporting host-based and data pump modems. The modem
DAC typical dynamic range is 90 dB over a 4.2 kHz analog
output passband where F
= 12.8 kHz. The left channel of the
S
ADC and DAC may be used to convert modem data at the same
sample rate in the range between 7 kHz and 48 kHz. All programmed sample rates have a resolution of 1 Hz. The AD1819B
supports irrational V.34 sample rates with 8/7 and 10/7 selectable sample rate multiplier coefficients.
Differences Between the AD1819A and AD1819B
The voltage reference (V
) of the AD1819B remains active
REF
while RESET is asserted. This eliminates the audible artifacts
associated with the RESET LO to HI transitions that can
occur during a Windows boot (power-up) or Windows warm
restart (reset).
–2–
REV. 0
SPECIFICATIONS
STANDARD TEST CONDITIONS UNLESS OTHERWISE NOTED
AD1819B
DAC Test Conditions
Temperature25°CCalibrated
Digital Supply (V
Analog Supply (V
Sample Rate (F
)5.0V0 dB Attenuation
DD
)5.0VInput 0 dB
CC
)48kHz10 kΩ Output Load
S
Input Signal1008HzMute Off
Analog Output Passband20 Hz to 20 kHz
(AC-Link)2.0V
V
IH
(AC-Link)0.8V
V
IL
(CS0, CS1, CHAIN_IN)4.0V
V
IH
(CHAIN_CLK)1.0V
V
IL
ANALOG INPUT
ADC Test Conditions
Calibrated
0 dB Gain
Input –3 dB Relative to Full Scale
Line Input Selected
ParameterMinTypMaxUnits
Input Voltage (RMS Values Assume Sine Wave Input)
LINE_IN, AUX, CD, VIDEO, PHONE_IN, PC_BEEP1V rms
2.83V p-p
MIC1, MIC2 with +20 dB Gain (M20 = 1)0.1V rms
0.283V p-p
MIC1, MIC2 with 0 dB Gain (M20 = 0)1V rms
2.83V p-p
Input Impedance*10kΩ
Input Capacitance*15pF
PROGRAMMABLE GAIN AMPLIFIER—ADC
ParameterMinTypMaxUnits
Step Size (0 dB to 22.5 dB)1.5dB
PGA Gain Range Span22.5dB
ANALOG MIXER— INPUT GAIN/AMPLIFIERS/ATTENUATORS
ParameterMinTypMaxUnits
Dynamic Range (–60 dB Input THD+N, Referenced to Full Scale, A-Weighted)
CD to LINE_OUT90dB
Other to LINE_OUT*90dB
Step Size (+12 dB to –34.5 dB): (All Steps Tested)
MIC, LINE_IN, AUX, CD, VIDEO, PHONE_IN, DAC1.5dB
Input Gain/Attenuation Range
MIC, LINE_IN, AUX, CD, VIDEO, PHONE_IN, DAC46.5dB
Step Size␣ (0 dB to –45 dB): (All Steps Tested)
PC_BEEP3.0dB
Input Gain/Attenuation Range: PC_BEEP45dB
DIGITAL DECIMATION AND INTERPOLATION FILTERS*
ParameterMinTypMaxUnits
Passband00.4 × F
Hz
S
Passband Ripple±0.09dB
Transition Band0.4 × F
Stopband0.6 × F
S
S
0.6 × F
∞
Hz
S
Hz
Stopband Rejection–74dB
Group Delay12/F
S
sec
Group Delay Variation Over Passband0.0µs
*Guaranteed, not tested.
Specifications subject to change without notice.
REV. 0
–3–
AD1819B–SPECIFICATIONS
ANALOG-TO-DIGITAL CONVERTERS
ParameterMinTypMaxUnits
Resolution16Bits
Total Harmonic Distortion (THD)0.02%
–74dB
Dynamic Range (–60 dB Input THD+N Referenced to Full Scale,
Power Supply Range—Analog4.55.5V
Power Supply Range—Digital4.55.5V
Power Supply Current120mA
Power Dissipation600mW
Analog Supply Current60mA
Digital Supply Current60mA
Power Supply Rejection (100 mV p-p Signal @ 1 kHz)*
(At Both Analog and Digital Supply Pins, Both ADCs and DACs)–40dB
CLOCK SPECIFICATIONS*
ParameterMinTypMaxUnits
Input Clock Frequency 24.576MHz
Recommended Clock Duty Cycle40 5060%
DD
DD
V
V
V
V
POWER-DOWN STATES
ParameterSet BitsMinTypMaxUnits
ADCs and Input Mux Power-DownPR0110mA
DACs Power-DownPR1100mA
Analog Mixer Power-Down (V
Analog Mixer Power-Down (V
REF
REF
and V
and V
On)PR1, PR254mA
REFOUT
Off)PR0, PR1, PR347mA
REFOUT
Digital Interface Power-Down*PR4120mA
Internal Clocks Disabled*PR0, PR1, PR4, PR585mA
ADC and DAC Power-DownPR0, PR185mA
Standby Mode*PR0, PR1, PR2, PR4, PR555mA
V
REF
Total Power-DownPR0, PR1, PR2, PR3,
PR4, PR5220µA
RESET (Low)250µA
*Guaranteed, not tested.
Specifications subject to change without notice.
REV. 0
–5–
AD1819B
TIMING PARAMETERS (GUARANTEED OVER OPERATING TEMPERATURE RANGE)
ParameterSymbolMinTypMaxUnits
RESET Active Low Pulsewidtht
RESET Inactive to BIT_CLK Start-Up Delayt
SYNC Active High Pulsewidtht
SYNC Low Pulsewidtht
SYNC Inactive to BIT_CLK Start-Up Delayt
RST_LOW
RST2CLK
SYNC_HIGH
SYNC_LOW
SYNC2CLK
BIT_CLK Frequency12.288MHz
BIT_CLK Periodt
CLK_PERIOD
BIT_CLK Output Jitter*750ps
BIT_CLK High Pulsewidtht
BIT_CLK Low Pulsewidtht
CLK_HIGH
CLK_LOW
SYNC Frequency48.0kHz
SYNC Periodt
Setup to Falling Edge of BIT_CLKt
Hold from Falling Edge of BIT_CLKt
BIT_CLK Rise Timet
BIT_CLK Fall Timet
SYNC Rise Timet
SYNC Fall Timet
SDATA_IN Rise Timet
SDATA_IN Fall Timet
SDATA_OUT Rise Timet
SDATA_OUT Fall Timet
End of Slot 2 to BIT_CLK, SDATA_IN Lowt
SYNC_PERIOD
SETUP
HOLD
RISE CLK
FALL CLK
RISE SYNC
FALL SYNC
RISE DIN
FALL DIN
RISE DOUT
FALL DOUT
S2_PDOWN
Setup to Trailing Edge of RESET (Applies to
SYNC, SDATA_OUT)t
Rising Edge of RESET to HI-Z Delayt
*Output Jitter is directly dependent on crystal input jitter.
SETUP2RST
OFF
1.0µs
162.8ns
0.08141.3µs
19.5µs
162.8ns
81.4ns
32.5640.748.84ns
32.5640.748.84ns
20.8µs
15.0ns
15.0ns
4ns
4ns
4ns
4ns
4ns
4ns
4ns
4ns
1.0µs
15ns
25ns
RESET
BIT_CLK
SYNC
BIT_CLK
t
RST_LOW
Figure 1. Cold Reset
t
SYNC_HIGH
Figure 2. Warm Reset
BIT_CLK
SYNC
t
CLK_HIGH
Figure 3. Clock Timing
t
CLK_PERIOD
t
SYNC_HIGH
t
SYNC_PERIOD
t
RST2CLK
t
RST2CLK
t
CLK_LOW
t
SYNC_LOW
–6–
REV. 0
BIT_CLK
BIT_CLK
SDATA_OUT
SYNC
SDATA_IN
SLOT 1
SLOT 2
WRITE
TO 0x26
DATA
PR4
DON’T
CARE
t
S2_PDOWN
NOTE: BIT_CLK NOT TO SCALE
RESET
SDATA_OUT
HI-Z
t
SETUP2RST
t
OFF
SDATA_IN, BIT_CLK
WARNING!
ESD SENSITIVE DEVICE
SYNC
SDATA_OUT
t
SETUP
t
HOLD
Figure 4. Data Setup and Hold
AD1819B
BIT_CLK
SYNC
SDATA_IN
SDATA_OUT
t
RISECLK
t
RISESYNC
t
RISEDIN
t
RISEDOUT
t
FALLCLK
t
FALLSYNC
t
FALLDIN
t
FALLDOUT
Figure 5. Signal Rise and Fall Time
ABSOLUTE MAXIMUM RATINGS*
ParameterMinMaxUnits
Power Supplies
␣ ␣ Analog (AV
␣ ␣ Digital (DV
)–0.36.0V
DD
)–0.36.0V
DD
Input Current (Except Supply Pins)±10.0mA
Analog Input Voltage (Signal Pins)–0.3AV
Digital Input Voltage (Signal Pins)–0.3DV
+ 0.3 V
DD
+ 0.3 V
DD
Ambient Temperature (Operating)–40+85°C
Storage Temperature–65+150°C
*Stresses greater than those listed under Absolute Maximum Ratings may cause
permanent damage to the device. This is a stress rating only; functional operation
of the device at these or any other conditions above those indicated in the
operational section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
Figure 6. AC-Link, Link Low Power Mode Timing
Figure 7. ATE Test Mode
ORDERING GUIDE
TemperaturePackagePackage
ModelRangeDescriptionOption*
AD1819BJST –40°C to +85°C 48-Terminal LQFP ST-48
*ST = Thin Quad Flatpack.
ENVIRONMENTAL CONDITIONS
Ambient Temperature Rating
= T
T
AMB
= Case Temperature in °C
T
CASE
= Power Dissipation in W
P
D
= Thermal Resistance (Case-to-Ambient)
θ
CA
= Thermal Resistance (Junction-to-Ambient)
θ
JA
= Thermal Resistance (Junction-to-Case)
θ
JC
CASE
– (P
D
× θ
CA
)
Package
JA
LQFP76.2°C/W17°C/W59.2°C/W
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection.
Although the AD1819B features proprietary ESD protection circuitry, permanent damage may
occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD
precautions are recommended to avoid performance degradation or loss of functionality.
REV. 0
–7–
JC
CA
AD1819B
PIN CONFIGURATION
48-Terminal LQFP
(ST-48)
DV
DD1
XTL_IN
XTL_OUT
DV
SS1
SDATA_OUT
BIT_CLK
DV
SS2
SDATA_IN
DV
DD2
SYNC
RESET
PC_BEEP
CHAIN_CLK
CHAIN_INNCCS0NCNCNCNC
CS1
48 47 46 45 4439 38 3743 42 41 40
1
PIN 1
2
IDENTIFIER
3
4
5
6
7
8
9
10
11
12
13 14 15 16 17 18 19 20 21 22 23 24
PHONE_IN
NC = NO CONNECT
AUX_L
AUX_R
AD1819B
TOP VIEW
(Not to Scale)
CD_L
VIDEO_R
VIDEO_L
SS2
AV
CD_GND
CD_R
MIC1
DD2
AV
MIC2
LINE_IN_L
MONO_OUT
LINE_OUT_R
36
35
LINE_OUT_L
CX3D
34
33
RX3D
FILT_L
32
31
FILT_R
AFILT2
30
29
AFILT1
28
V
REFOUT
27
V
REF
AV
26
25
AV
LINE_IN_R
SS1
DD1
PIN FUNCTION DESCRIPTIONS
Digital I/O
Pin NameLQFPI/ODescription
XTL_IN2I24.576 MHz Crystal or Clock Input
XTL_OUT3O24.576 MHz Crystal Output
SDATA_OUT5ISerial Data Output. Serial, Time Division Multiplexed, AD1819B Input Stream
BIT_CLK6O/I*Bit Clock Input, 12.288 MHz Serial Data Clock. Daisy Chain Output Clock
SDATA_IN8OSerial Data Input. Serial, Time Division Multiplexed, AD1819B Output Stream
SYNC10I48 kHz Fixed Rate Sample Sync Clock
RESET11IReset. AC-Link Master Hardware Reset
*Input if the AD1819B is configured as Slave 1 or Slave 2.
*Output when configured as Master. Input when configured as Slave 1 or Slave 2.
–8–
REV. 0
AD1819B
Analog I/O
These signals connect the AD1819B component to analog sources and sinks, including microphones and speakers.
Pin NameLQFPI/ODescription
PC_BEEP12IPC Beep. PC Speaker Beep Pass-Through
PHONE_IN13IPhone. From Telephony Subsystem Speakerphone or Handset
AUX_L14IAuxiliary Input Left Channel
AUX_R15IAuxiliary Input Right Channel
VIDEO_L16IVideo Audio Left Channel
VIDEO_R17IVideo Audio Right Channel
CD_L18ICD Audio Left Channel
CD_GND19ICD Audio Analog Ground Sense for Differential CD Input
CD_R20ICD Audio Right Channel
MIC121IMicrophone 1. Desktop Microphone Input
MIC222IMicrophone 2. Second Microphone Input
LINE_IN_L23ILine In Left Channel
LINE_IN_R24ILine In Right Channel
LINE_OUT_L35OLine Out Left Channel
LINE_OUT_R36OLine Out Right Channel
MONO_OUT37OMonaural Output to Telephony Subsystem Speakerphone
Filter/Reference
Pin NameLQFPI/ODescription
V
REF
V
REFOUT
AFILT129OAntialiasing Filter Capacitor—ADC Right Channel
AFILT230OAntialiasing Filter Capacitor—ADC Left Channel
FILT_R31OAC-Coupling Filter Capacitor—ADC Right Channel
FILT_L32OAC-Coupling Filter Capacitor—ADC Left Channel
RX3D33O3D Phat Stereo Enhancement—Capacitor
CX3D34I3D Phat Stereo Enhancement—Capacitor
27OVoltage Reference Filter
28OVoltage Reference Output 5 mA Drive (Intended for Mic Bias)
Power and Ground Signals
Pin NameLQFPI/ODescription
DV
DD1
DV
SS1
DV
SS2
DV
DD2
AV
DD1
AV
SS1
AV
DD2
AV
SS2
No Connects
1IDigital VDD—5.0 V
4IDigital GND
7IDigital GND
9IDigital VDD—5.0 V
25IAnalog VDD—5.0 V
26IAnalog GND
38IAnalog VDD—5.0 V
42IAnalog GND