AD1852 [ADI]
Stereo, 24-Bit, 192 kHz Multibit DAC; 立体声, 24位, 192千赫多位DAC型号: | AD1852 |
厂家: | ADI |
描述: | Stereo, 24-Bit, 192 kHz Multibit DAC |
文件: | 总16页 (文件大小:227K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
Stereo, 24-Bit, 192 kHz
a
Multibit Σ∆ DAC
AD1852*
FEATURES
5 V Stereo Audio DAC System
Flexible Serial Data Port with Right-Justified, Left-
Justified, I2S-Compatible and DSP Serial Port Modes
28-Lead SSOP Plastic Package
Accepts 16-Bit/18-Bit/20-Bit/24-Bit Data
Supports 24 Bits, 192 kHz Sample Rate
Accepts a Wide Range of Sample Rates Including:
32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, and
192 kHz
Multibit Sigma-Delta Modulator with “Perfect
Differential Linearity Restoration” for Reduced Idle
Tones and Noise Floor
Data-Directed Scrambling DAC—Least Sensitive to
Jitter
Differential Output for Optimum Performance
117 dB Signal-to-Noise (Not Muted) at 48 kHz Sample
Rate (A-Weighted Mono)
114 dB Signal-to-Noise (Not Muted) at 48 kHz Sample
Rate (A-Weighted Stereo)
117 dB Dynamic Range (Not Muted) at 48 kHz Sample
Rate (A-Weighted Mono)
114 dB Dynamic Range (Not Muted) at 48 kHz Sample
Rate (A-Weighted Stereo)
APPLICATIONS
Hi End: DVD, CD, Home Theater Systems, Automotive
Audio Systems, Sampling Musical Keyboards, Digital
Mixing Consoles, Digital Audio Effects Processors
PRODUCT OVERVIEW
The AD1852 is a complete high performance single-chip stereo
digital audio playback system. It is comprised of a multibit sigma-
delta modulator, digital interpolation filters, and analog output
drive circuitry. Other features include an on-chip stereo attenuator
and mute, programmed through an SPI-compatible serial control
port. The AD1852 is fully compatible with all known DVD
formats including 192 kHz as well as 96 kHz sample frequen-
cies and 24 bits. It also is backwards compatible by supporting
50 µs/15 µs digital de-emphasis intended for “Redbook” compact
discs, as well as de-emphasis at 32 kHz and 48 kHz sample rate.
The AD1852 has a very simple but very flexible serial data input
port that allows for glueless interconnection to a variety of ADCs,
DSP chips, AES/EBU receivers and sample rate converters. The
AD1852 can be configured in left-justified, I2S, right-justified,
or DSP serial port compatible modes. It can support 16, 18, 20,
and 24 bits in all modes. The AD1852 accepts serial audio data
in MSB first, twos-complement format. The AD1852 oper-
ates from a single 5 V power supply. It is fabricated on a single
monolithic integrated circuit and is housed in a 28-lead SSOP
package for operation over the temperature range 0°C to 70°C.
–105 dB THD+N (Mono Application Circuit)
–102 dB THD+N (Stereo)
115 dB Stopband Attenuation
On-Chip Clickless Volume Control
Hardware and Software Controllable Clickless Mute
Serial (SPI) Control for: Serial Mode, Number of Bits,
Sample Rate, Volume, Mute, De-Emp
Digital De-Emphasis Processing for 32 kHz, 44.1 kHz,
48 kHz Sample Rates
Clock Autodivide Circuit Supports Five Master-Clock
Frequencies
FUNCTIONAL BLOCK DIAGRAM
DIGITAL
SUPPLY
CLOCK
IN
CONTROL DATA
INPUT
VOLUME
MUTE
2
3
VOLTAGE
REFERENCE
AUTO-CLOCK
DIVIDE CIRCUIT
SERIAL CONTROL
INTERFACE
AD1852
16-/18-/20-/24-BIT
DIGITAL
8
؋
F INTERPOLATOR
MULTIBIT SIGMA-
DELTA MODULATOR
ATTEN/
MUTE
S
DAC
DATA INPUT
SERIAL
DATA
ANALOG
OUTPUTS
INTERFACE
2
SERIAL
MODE
8
؋
F INTERPOLATION
MULTIBIT SIGMA-
DELTA MODULATOR
ATTEN/
MUTE
S
DAC
2
ANALOG
2
MUTE
DE-EMPHASIS
ZERO
FLAG
RESET
SUPPLY
*Patents Pending
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.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
Fax: 781/326-8703
World Wide Web Site: http://www.analog.com
© Analog Devices, Inc., 2000
AD1852–SPECIFICATIONS
TEST CONDITIONS UNLESS OTHERWISE NOTED
Supply Voltages (AVDD, DVDD
Ambient Temperature
Input Clock
)
5.0 V
25°C
24.576 MHz (512 × FS Mode)
Input Signal
996.11 Hz
–0.5 dB Full Scale
48 kHz
20 Hz to 20 kHz
20 Bits
Input Sample Rate
Measurement Bandwidth
Word Width
Load Capacitance
Load Impedance
Input Voltage HI
Input Voltage LO
100 pF
47 kΩ
2.4 V
0.8 V
ANALOG PERFORMANCE (See Figures)
Min
Typ
Max
Unit
Resolution
24
Bits
Signal-to-Noise Ratio (20 Hz to 20 kHz)
No Filter (Stereo)
No Filter (Mono—See Figure 29)
With A-Weighted Filter (Stereo)
With A-Weighted Filter (Mono—See Figure 29)
Dynamic Range (20 Hz to 20 kHz, –60 dB Input)
No Filter (Stereo)
No Filter (Mono—See Figure 29)
With A-Weighted Filter (Stereo)
With A-Weighted Filter (Mono—See Figure 29)
Total Harmonic Distortion + Noise (Stereo)
112
115
114
117
dB
dB
dB
dB
107
110
–94
112
115
114
117
–102
0.00079
–105
0.00056
–92
dB
dB
dB
dB
dB
%
dB
%
dB
dB
Total Harmonic Distortion + Noise (Mono—See Figure 29)
Total Harmonic Distortion + Noise (Stereo) VO = –20 dB
Total Harmonic Distortion + Noise (Stereo) VO = –60 dB
Analog Outputs
–52
Differential Output Range (± Full Scale)
Output Capacitance at Each Output Pin
Out-of-Band Energy (0.5 × FS to 100 kHz)
CMOUT
5.6
V p-p
pF
dB
2
–90
2.37
V
DC Accuracy
Gain Error
Interchannel Gain Mismatch
Gain Drift
DC Offset
–10
–0.15
±2.0
±0.015
150
+10
+0.15
250
%
dB
ppm/°C
mV
–50
Interchannel Crosstalk (EIAJ Method)
Interchannel Phase Deviation
Mute Attenuation
–120
±0.1
–100
dB
Degrees
dB
De-Emphasis Gain Error
±0.1
dB
Performance of right and left channels are identical (exclusive of the Interchannel Gain Mismatch and Interchannel Phase Deviation specifications).
Specifications subject to change without notice.
DIGITAL I/O (0؇C TO 70؇C)
Min
Typ
Max
Unit
Input Voltage HI (VIH)
Input Voltage LO (VIL)
Input Leakage (IIH @ VIH = 2.4 V)
Input Leakage (IIL @ VIL = 0.8 V)
High Level Output Voltage (VOH) IOH = 1 mA
Low Level Output Voltage (VOL) IOL = 1 mA
Input Capacitance
2.2
V
V
µA
µA
V
V
pF
0.8
10
10
2.0
0.4
20
Specifications subject to change without notice.
REV. 0
–2–
AD1852
TEMPERATURE RANGE
Min
Typ
Max
Unit
Specifications Guaranteed
Functionality Guaranteed
Storage
25
°C
°C
°C
0
–55
70
+150
Specifications subject to change without notice.
POWER
Min
Typ
Max
Unit
Supplies
Voltage, Analog and Digital
Analog Current
Analog Current—RESET
Digital Current
Digital Current—RESET
Dissipation
4.50
5
5.50
40
46
30
37
V
33
32
20
27
mA
mA
mA
Operation—Both Supplies
Operation—Analog Supply
Operation—Digital Supply
Power Supply Rejection Ratio
1 kHz 300 mV p-p Signal at Analog Supply Pins
20 kHz 300 mV p-p Signal at Analog Supply Pins
265
165
100
mW
mW
mW
–60
–50
dB
dB
Specifications subject to change without notice.
DIGITAL FILTER CHARACTERISTICS
Sample Rate (kHz)
Passband (kHz)
Stopband (kHz)
Stopband Attenuation (dB)
Passband Ripple (dB)
44.1
48
96
DC–20
24.1–328.7
26.23–358.28
56.9–327.65
117–327.65
110
110
115
95
±0.0002
±0.0002
±0.0005
+0/–0.04 (DC–21.8 kHz)
+0/–0.5 (DC–65.4 kHz)
+0/–1.5 (DC–87.2 kHz)
DC–21.8
DC–39.95
DC–87.2
192
Specifications subject to change without notice.
GROUP DELAY
Chip Mode
Group Delay Calculation
FS
Group Delay
Unit
INT8x Mode
INT4x Mode
INT2x Mode
5553/(128 × FS)
5601/(64 × FS)
5659/(32 × FS)
48 kHz
96 kHz
192 kHz
903.8
911.6
921
µs
µs
µs
Specifications subject to change without notice.
DIGITAL TIMING (Guaranteed Over 0؇C to 70؇C, AVDD = DVDD = +5.0 V ؎ 10%)
Min
Unit
tDMP
tDML
tDMH
tDBH
tDBL
tDBP
tDLS
tDLH
tDDS
tDDH
tRSTL
MCLK Period (FMCLK = 256 × FL/RCLK)*
MCLK LO Pulsewidth (All Modes)
MCLK HI Pulsewidth (All Modes)
BCLK HI Pulsewidth
BCLK LO Pulsewidth
BCLK Period
L/RCLK Setup
L/RCLK Hold (DSP Serial Port Mode Only)
SDATA Setup
SDATA Hold
RST LO Pulsewidth
54
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
0.4 × tDMP
0.4 × tDMP
20
20
60
20
5
5
10
15
*Higher MCLK frequencies are allowable when using the on-chip Master Clock Autodivide Feature.
Specifications subject to change without notice.
REV. 0
–3–
AD1852
ABSOLUTE MAXIMUM RATINGS*
PIN CONFIGURATION
Min
Max
Unit
DVDD to DGND
AVDD to AGND
Digital Inputs
Analog Outputs
AGND to DGND
Reference Voltage
Soldering
–0.3
–0.3
6
6
V
V
V
V
V
V
°C
sec
1
2
28
27
26
25
24
DGND
MCLK
CLATCH
CCLK
DVDD
SDATA
BCLK
DGND – 0.3 DVDD + 0.3
AGND – 0.3
–0.3
3
AVDD + 0.3
0.3
(AVDD + 0.3)/2
300
10
4
LRCLK
CDATA
NC
5
RESET
6
23 MUTE
AD1852
TOP VIEW
(Not to Scale)
7
22 ZEROL
192/48
ZEROR
DEEMP
8
21
IDPM0
9
20 IDPM1
19 FILTB
*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.
10
11
12
13
14
96/48
AGND
OUTR+
OUTR–
FILTR
18
17
16
15
AVDD
OUTL+
OUTL–
AGND
PACKAGE CHARACTERISTICS
Min
Typ
Max Unit
θJA (Thermal Resistance
[Junction-to-Ambient])
θJC (Thermal Resistance
[Junction-to-Case])
109
°C/W
39
°C/W
ORDERING GUIDE
Package Description
Model
Temperature
Package Option
AD1852JRS
AD1852JRSRL
0°C to 70°C
0°C to 70°C
28-Lead Shrink Small Outline Package (SSOP)
28-Lead Shrink Small Outline Package (SSOP)
RS-28
RS-28 on 13" Reels
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 AD1852 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.
WARNING!
ESD SENSITIVE DEVICE
REV. 0
–4–
AD1852
PIN FUNCTION DESCRIPTIONS
Pin
Input/Output
Pin Name
Description
1
2
I
I
DGND
MCLK
Digital Ground.
Master Clock Input. Connect to an external clock source at either 256 FS, 384 FS,
512 FS, 768 FS, or 1024 FS.
3
4
I
I
CLATCH
CCLK
Latch Input for Control Data. This input is rising-edge sensitive.
Control Clock Input for Control Data. Control input data must be valid on the rising
edge of CCLK. CCLK may be continuous or gated.
5
I
CDATA
Serial Control Input, MSB first, containing 16 bits of unsigned data per channel. Used
for specifying channel-specific attenuation and mute.
6
7
8
NC
192/48
ZEROR
No Connect.
I
O
Selects 48 kHz (LO) or 192 kHz Sample Frequency.
Right Channel Zero Flag Output. This pin goes HI when Right Channel has no signal
input for more than 1024 LR Clock Cycles.
9
I
DEEMP
De-Emphasis. Digital de-emphasis is enabled when this input signal is HI. This is used
to impose a 50 µs/15 µs response characteristic on the output audio spectrum at an
assumed 44.1 kHz sample rate. Curves for 32 kHz and 48 kHz sample rates may be
selected via SPI control register.
10
11, 15
12
13
14
I
I
O
O
O
96/48
Selects 48 kHz (LO) or 96 kHz Sample Frequency.
Analog Ground.
Right Channel Positive Line Level Analog Output.
Right Channel Negative Line Level Analog Output.
AGND
OUTR+
OUTR–
FILTR
Voltage Reference Filter Capacitor Connection. Bypass and decouple the voltage refer-
ence with parallel 10 µF and 0.1 µF capacitors to the AGND.
16
17
18
19
20
21
22
O
O
I
OUTL–
OUTL+
AVDD
FILTB
IDPM1
IDPM0
ZEROL
Left Channel Negative Line Level Analog Output.
Left Channel Positive Line Level Analog Output.
Analog Power Supply. Connect to Analog 5 V Supply.
Filter Capacitor Connection. Connect 10 µF capacitor to AGND (Pin 15).
Input Serial Data Port Mode Control One. With IDPM0, defines 1 of 4 serial modes.
Input Serial Data Port Mode Control Zero. With IDPM1, defines 1 of 4 serial modes.
Left Channel Zero Flag Output. This pin goes HI when Left Channel has no signal
input for more than 1024 LR Clock Cycles.
I
I
O
23
24
I
I
MUTE
RESET
Mute. Assert HI to mute both stereo analog outputs. Deassert LO for normal operation.
Reset. The AD1852 is reset on the rising edge of this signal. The serial control port
registers are reset to the default values. Connect HI for normal operation.
25
26
I
I
L/RCLK
BCLK
Left/Right Clock Input for Input Data. Must run continuously.
Bit Clock Input for Input Data. Need not run continuously; may be gated or used in a
burst fashion.
27
28
I
I
SDATA
DVDD
Serial Input, MSB first, containing two channels of 16, 18, 20, and 24 bits of twos
complement data per channel.
Digital Power Supply Connect to digital 5 V supply.
Table I. Serial Data Input Mode
IDPM1 (Pin 20) IDPM0 (Pin 21) Serial Data Input Format
0
0
1
1
0
1
0
1
Right-Justified
I2S-Compatible
Left-Justified
DSP
REV. 0
–5–
AD1852
L/RCLK
INPUT
LEFT CHANNEL
RIGHT CHANNEL
BCLK
INPUT
SDATA
LSB
MSB MSB–1 MSB–2
LSB+2 LSB+1 LSB
MSB–1
LSB+1
LSB+2
MSB
MSB–2
LSB
INPUT
Figure 1. Right-Justified Mode
L/RCLK
INPUT
LEFT CHANNEL
RIGHT CHANNEL
BCLK
INPUT
SDATA
INPUT
MSB MSB–1 MSB–2
LSB+2 LSB+1 LSB
MSB MSB–1 MSB–2
LSB+2 LSB+1 LSB
MSB
Figure 2. I2S-Justified Mode
L/RCLK
INPUT
LEFT CHANNEL
RIGHT CHANNEL
BCLK
INPUT
SDATA
INPUT
MSB
MSB–1 MSB–2
LSB+2 LSB+1
LSB
MSB
MSB–1 MSB–2
LSB+2 LSB+1
LSB
MSB
MSB–1
Figure 3. Left-Justified Mode
L/RCLK
INPUT
RIGHT CHANNEL
LEFT CHANNEL
BCLK
INPUT
SDATA
INPUT
MSB MSB–1
LSB+2 LSB+1
LSB
MSB MSB–1
LSB+2 LSB+1
LSB
MSB MSB–1
Figure 4. Left-Justified DSP Mode
L/RCLK
INPUT
LEFT CHANNEL
RIGHT CHANNEL
BCLK
INPUT
SDATA
INPUT
LSB
MSB
MSB–1 MSB–2
LSB+2
LSB+1
LSB
MSB
MSB–1 MSB–2
LSB+2
LSB+1
LSB
MSB
MSB–1
Figure 5. 32 × FS Packed Mode
REV. 0
–6–
AD1852
OPERATING FEATURES
Serial Data Input Port
port will begin to accept data starting at the eighth bit clock
pulse after the L/RCLK transition. When the wordlength con-
trol bits are set to 20-bit mode, data is accepted starting at
the twelfth-bit clock position. In 16-bit mode, data is accepted
starting at the sixteenth-bit clock position. These delays are
independent of the number of bit clocks per frame, and therefore
other data formats are possible using the delay values described
above. For detailed timing, see Figure 6.
Figure 2 shows the I2S mode. L/RCLK is LO for the left chan-
nel and HI for the right channel. Data is valid on the rising edge
of BCLK. The MSB is left-justified to an L/RCLK transition
but with a single BCLK period delay. The I2S mode can be used
to accept any number of bits up to 24.
The AD1852’s flexible serial data input port accepts data in
twos-complement, MSB-first format. The left channel data field
always precedes the right channel data field. The serial mode is
set by using either the external mode pins (IDPM0 Pin 21 and
IDPM1 Pin 20) or the mode select bits (Bits 4 and 5) in the SPI
control register. To control the serial mode using the external
mode pins, the SPI mode select bits should be set to zero (default
at power-up). To control the serial mode using the SPI mode
select bits, the external mode control pins should be grounded.
In all modes except for the right-justified mode, the serial port
will accept an arbitrary number of bits up to a limit of 24. Extra
bits will not cause an error, but they will be truncated internally.
In the right-justified mode, control register Bits 8 and 9 are used
to set the wordlength to 16 bits, 20 bits, or 24 bits. The default
on power- up is 24-bit mode. When the SPI Control Port is not
being used, the SPI pins (3, 4, and 5) should be tied LO.
Figure 3 shows the left-justified mode. L/RCLK is HI for the
left channel, and LO for the right channel. Data is valid on the
rising edge of BCLK. The MSB is left-justified to an L/RCLK
transition, with no MSB delay. The left-justified mode can
accept any wordlength up to 24 bits, and any number of bit clocks
from two times the word length to 64 bit clocks per frame.
Serial Data Input Mode
The AD1852 uses two multiplexed input pins to control the mode
configuration of the input data port mode. See Table I.
Figure 4 shows the DSP serial port mode. L/RCLK must pulse
HI for at least one bit clock period before the MSB of the left
channel is valid, and L/RCLK must pulse HI again for at least
one bit clock period before the MSB of the right channel is valid.
Data is valid on the falling edge of BCLK. The DSP serial port
mode can be used with any wordlength up to 24 bits.
Figure 1 shows the right-justified mode (16 bits shown). L/RCLK
is HI for the left channel, LO for the right channel. Data is valid
on the rising edge of BCLK.
In normal operation, there are 64-bit clocks per frame (or 32
per half-frame). When the SPI wordlength control bits (Bits 8
and 9 in the control register) are set to 24 bits (0:0), the serial
In this mode, it is the responsibility of the DSP to ensure that
the left data is transmitted with the first L/RCLK pulse, and
that synchronism is maintained from that point forward.
tDBH
tDBP
BCLK
tDBL
tDLS
L/RCLK
tDDS
SDATA
LEFT-JUSTIFIED
MODE
MSB
tDDH
MSB-1
tDDS
MSB
tDDH
SDATA
I S-JUSTIFIED
2
MODE
tDDS
LSB
tDDH
tDDS
MSB
SDATA
RIGHT-JUSTIFIED
MODE
tDDH
8-BIT CLOCKS
(24-BIT DATA)
12-BIT CLOCKS
(20-BIT DATA)
16-BIT CLOCKS
(16-BIT DATA)
Figure 6. Serial Data Port Timing
REV. 0
–7–
AD1852
Table II.
Nominal Input
Sample Rate
Internal Sigma-
Delta Clock Rate
Chip Mode
Allowable Master Clock Frequencies
INT8× Mode
INT4× Mode
INT2× Mode
256 × FS, 384 × FS, 512 × FS, 768 × FS, 1024 × FS
128 × FS, 192 × FS, 256 × FS, 384 × FS, 512 × FS
64 × FS, 96 × FS, 128 × FS, 192 × FS, 256 × FS
48 kHz
96 kHz
192 kHz
128 × FS
64 × FS
32 × FS
SPI REGISTER DEFINITIONS
Note that the AD1852 is capable of a 32 × FS BCLK frequency
“packed mode” where the MSB is left-justified to an L/RCLK
transition, and the LSB is right-justified to the opposite L/RCLK
transition. L/RCLK is HI for the left channel, and LO for the
right channel. Data is valid on the rising edge of BLCK. Packed
mode can be used when the AD1852 is programmed in right-
justified or left-justified mode. Packed mode is shown is Figure 5.
The SPI port allows flexible control of many chip parameters. It is
organized around three registers; a LEFT-CHANNEL VOLUME
register, a RIGHT-CHANNEL VOLUME register, and a
CONTROL register. Each WRITE operation to the AD1852
SPI control port requires 16 bits of serial data in MSB-first format.
The bottom two bits are used to select one of three registers,
and the top 14 bits are then written to that register. This allows
a write to one of the three registers in a single 16-bit transaction.
Master Clock Autodivide Feature
The AD1852 has a circuit that autodetects the relationship
between master clock and the incoming serial data, and inter-
nally sets the correct divide ratio to run the interpolator and
modulator. The allowable frequencies for each mode are shown
above. Master clock should be synchronized with L/RCLK but
phase relation between master clock and L/RCLK is not critical.
The SPI CCLK signal is used to clock in the data. The incom-
ing data should change on the falling edge of this signal. At the
end of the 16 CCLK periods, the CLATCH signal should rise
to clock the data internally into the AD1852.
tCHD
CDATA
CCLK
D15
D14
D0
tCCH
tCLH
tCSU
tCCL
tCLL
CLATCH
tCLSU
Figure 7. Serial Control Port Timing
REV. 0
–8–
AD1852
Table III. SPI Digital Timing
Min
Unit
0
VOLUME REQUEST REGISTER
tCCH
tCCL
tCSU
tCHD
tCLL
tCLH
tCLSU
CCLK HI Pulsewidth
CCLK LOW Pulsewidth
CDATA Setup Time
40
40
10
ns
ns
ns
ns
ns
ns
ns
–60
0
CDATA Hold Time
10
10
10
4 × tMCLK
CLATCH LOW Pulsewidth
CLATCH HI Pulsewidth
CLATCH Setup Time
ACTUAL VOLUME REGISTER
–60
Register Addresses
The lowest two bits of the 16-bit input word are decoded as fol-
lows to set the register that the upper 14 bits will written into.
TIME
20ms
Figure 8. Smooth Volume Control
SPI Timing
VOLUME LEFT AND VOLUME RIGHT REGISTERS
A write operation to the left or right volume registers will acti-
vate the “autoramp” clickless volume control feature of the
AD1852. This feature works as follows. The upper 10 bits of the
volume control word will be incremented or decremented by 1 at
a rate equal to the input sample rate. The bottom four bits are
not fed into the autoramp circuit and thus take effect immediately.
This arrangement gives a worst-case ramp time of about 20 ms
for step changes of more than 60 dB, which has been deter-
mined by listening tests to be optimal in terms of preventing the
perception of a “click” sound on large volume changes. See Fig-
ure 8 for a graphical description of how the volume changes
as a function of time.
The SPI port is a 3-wire interface with serial data (CDATA),
serial bit clock (CCLK), and data latch (CLATCH). The
data is clocked into an internal shift register on the rising
edge of CCLK. The serial data should change on the falling
edge of CCLK and be stable on the rising edge of CCLK.
The rising edge of CLATCH is used internally to latch the par-
allel data from the serial-to-parallel converter. This rising edge
should be aligned with the falling edge of the last CCLK pulse
in the 16-bit frame. The CCLK can run continuously between
transactions.
Note that the serial control port timing is asynchronous to the
serial data port timing. Changes made to the attenuator level
will be updated on the next edge of the L/RCLK after the
CLATCH write pulse as shown in Figure 7.
The 14-bit volume control word is used to multiply the signal,
and therefore the control characteristic is linear, not dB. A constant
dB/step characteristic can be obtained by using a lookup table
in the microprocessor that is writing to the SPI port. The volume
word is unsigned (i.e., 0 dB is 11 1111 1111 1111).
Mute
The AD1852 offers two methods of muting the analog output.
By asserting the MUTE (Pin 23) signal HI, both the left and
right channel are muted. As an alternative, the user can assert
the mute bit in the serial control register (data11) HI. The
AD1852 has been designed to minimize pops and clicks when
muting and unmuting the device by automatically “ramping”
the gain up or down. When the device is unmuted, the volume
returns to the value set in the volume register.
Table IV.
Bit 1
Bit 0
Register
0
1
0
0
0
1
Volume Left
Volume Right
Control Register
REV. 0
–9–
AD1852
Table V.
Bit 11
Bit 10
Bit 9:8
Bit 7
Bit 6
Bit 5:4
Bit 3:2
INT2× Mode
OR’d with Pin 7 OR’d with Pin 10 Bits in Right-
(192/48).
Default = 0
INT4× Mode
Number of
Reset.
Soft Mute OR’d Serial Mode OR’d De-Emphasis Filter
Default = 0 with Pin.
Default = 0
with Mode Pins.
IDPM1:IDPM0
Select.
0:0 No Filter
(96/48).
Default = 0
Justified Serial
Mode.
0:0 = 24
0:1 = 20
1:0 = 16
0:0 Right-Justified 0:1 44.1 kHz Filter
0:1 I2S
1:0 Left-Justified
1:1 DSP Mode
Default = 0:0
1:0 32 kHz Filter
1:1 48 kHz Filter
Default = 0:0
Default = 0:0
Control Register
the outputs assume midscale values. The AD1852 should always
be reset at power up. The RESET function should be active for
a minimum of 64 master clock periods. When the RESET func-
tion becomes inactive, normal operation will continue after a
delay equal to the group delay plus three MCLK periods.
Table V shows the functions of the control register. The control
register is addressed by having an ‘01’ in the bottom two bits of
the 16-bit SPI word. The top 14 bits are then used for the con-
trol register.
De-Emphasis
Using the RESET pin, the internal registers will be set to their
default values, when the RESET pin is active low. Default
operation will then be enabled when the RESET pin is raised.
Alternatively, the internal registers can be reset to their default
values by setting Bit 7, of the internal control register, high.
When Bit 7 is reset low, default operation will continue. The
software reset differs from the hardware reset because the soft
reset does not affect the values stored in the SPI registers.
The AD1852 has a built-in de-emphasis filter that can be used
to decode CDs that have been encoded with the standard
“redbook” 50 µs/15 µs emphasis response curve. Three curves
are available; one each for 32 kHz, 44.1 kHz, and 48 kHz sam-
pling rates. The external “DEEMP” pin (Pin 9) turns on the
44.1 kHz de-emphasis filter. The other filters may be selected by
writing to Control Bits 2 and 3 in the control register. If the SPI
port is used to control the de-emphasis filter, the external DEEMP
pin should be tied LO.
Control Signals
The IDPM0 and IDPM1 control inputs are normally connected
HI or LO to establish the operating state of the AD1852. They
can be changed dynamically (and asynchronously to L/RCLK
and the master clock), but it is possible that a click or pop sound
may result during the transition from one serial mode to another.
If possible, the AD1852 should be placed in mute before such a
change is made.
Output Impedance
The output impedance of the AD1852 is 65 Ω ± 30%.
Reset
The AD1852 may be reset either by a dedicated hardware pin
(RESET, Pin 24) or by software, via the SPI control port. While
reset is active, normal operation of the AD1852 is suspended and
REV. 0
–10–
Typical Performance Characteristics–
AD1852
Figures 9–14 show the calculated frequency response of the
digital interpolation filters. Figures 15–26 show the performance
of the AD1852 as measured by an Audio Precision System 2
Cascade. For the wideband plots, the noise floor shown in the
plots is higher than the actual noise floor of the AD1852. This is
caused by the higher noise floor of the “High Bandwidth” ADC
used in the Audio Precision measurement system. The two-tone
test shown in Figure 17 is per the SMPTE standard for measur-
ing Intermodulation Distortion.
0.001
0.0008
0.0006
0.0004
0.0002
0
0
–20
–40
–60
–80
–0.0002
–0.0004
–0.0006
–0.0008
–0.001
–100
–120
–140
–160
0
2
4
6
8
10
12
14
16
18
20
0
50
100
150
200
250
300
350
FREQUENCY – kHz
FREQUENCY – kHz
Figure 9. Passband Response 8× Mode, 48 kHz Sample
Figure 12. Complete Response, 8× Mode, 48 kHz
Rate
Sample Rate
0
0.5
0.4
–20
–40
0.3
0.2
–60
–80
0.1
0
–0.1
–0.2
–0.3
–0.4
–0.5
–100
–120
–140
–160
0
50
100
150
200
250
300
–10
5
10
15
20
25
30
35
40
FREQUENCY – kHz
FREQUENCY – kHz
Figure 10. 44 kHz Passband Response 4× Mode, 96 kHz
Figure 13. Complete Response, 4× Mode, 96 kHz
Sample Rate
Sample Rate
0
–20
2.0
1.5
–40
1.0
0.5
0
–60
–80
–100
–120
–140
–160
–0.5
–1.0
–1.5
–2.0
0
50
100
150
200
250
0
10
20
30
40
50
60
70
80
FREQUENCY – kHz
FREQUENCY – kHz
Figure 14. Complete Response, 2× Mode, 192 kHz
Figure 11. 88 kHz Passband Response 2× Mode, 192 kHz
Sample Rate
Sample Rate
REV. 0
–11–
AD1852
0
–50
–60
–70
–80
–90
–10
–20
–30
–40
–50
–60
–70
–100
–110
–80
–90
–100
–110
–120
10
–120
–100
–80
–60
dBFS
–40
–20
0
100
1k
10k
20k
FREQUENCY – Hz
Figure 18. THD + N Ratio vs. Amplitude Input 1 kHz,
SR 48 kS/s, 24-Bit
Figure 15. THD vs. Frequency Input @ –3 dBFS, SR 48 kHz
2
0
–90
–100
–110
–120
–130
–140
–2
–4
–6
–8
–150
–160
–10
–12
0
2
4
6
8
10
12
14
16
18
20 22
10
100
1k
10k 20k
FREQUENCY – kHz
FREQUENCY – Hz
Figure 19. Noise Floor for Zero Input, SR 48 kHz
Figure 16. Normal De-Emphasis Frequency Response
Input @ –10 dBFS, SR 48 kHz
0
–10
–20
–30
–40
–50
–60
–70
–80
–10
–30
–50
–70
–90
–90
–100
–110
–120
–130
–140
–150
–110
–130
–150
0
2
4
6
8
10
12
14
16
18
20 22
0
2
4
6
8
10
12
14
16
18
20 22
FREQUENCY – kHz
FREQUENCY – kHz
Figure 20. Input 0 dBFS @ 1 kHz, BW 10 Hz to 22 kHz,
SR 48 kHz
Figure 17. SMPTE/DIN 4:1 IMD 60 Hz/7 kHz @ 0 dBFS
REV. 0
–12–
AD1852
–50
–60
0
–20
–70
–80
–40
–60
–80
–90
–100
–110
–120
–130
–100
–120
–140
–140
–150
–160
–140
–120
–100
–80
–60
–40
–20
0
0
2
4
6
8
10
12
14
16
18
20 22
FREQUENCY – kHz
dBFS
Figure 21. Linearity vs. Amplitude Input 200 Hz,
SR 48 kS/s, 24-Bit Word
Figure 24. Dynamic Range for 1 kHz @ –60 dBFS,
Triangular Dithered Input
0
–10
–20
–64
–66
–30
–40
–50
–68
–60
–70
–80
–70
–72
–90
–100
–110
–120
–130
–140
–150
–160
–74
–76
1k
10k 20k
5
10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
FREQUENCY – kHz
10
100
FREQUENCY – Hz
Figure 22. Power Supply Rejection vs. Frequency
AVDD 5 V DC + 100 mV p-p AC
Figure 25. Wideband Plot, 75 kHz Input, 2× Interpolation,
SR 192 kHz
0
0
–10
–20
–30
–10
–20
–30
–40
–50
–40
–50
–60
–60
–70
–70
–80
–80
–90
–90
–100
–110
–120
–130
–140
–100
–110
–120
–130
–140
20
40
60
80
100
120
20
40
60
80
100
120
FREQUENCY – kHz
FREQUENCY – kHz
Figure 23. Wideband Plot, 15 kHz Input, 8× Interpolation,
SR 48 kHz
Figure 26. Wideband Plot, 37 kHz Input, 4× Interpolation,
SR 96 kHz
REV. 0
–13–
AD1852
MCLK/SR SELECT
SELECT RATE 2xMCLK 384/256 96/48 MCLK
DVDD
SPDIF
DIRECT
DIRECT 96.0
44.1
48.0
0
0
0
0
0
0
0
0
1
11,2896
11,2880
12,2880
R3
R2
R1
OUTPUT BUFFERS & LP FILTERS
C9
10k⍀ 10k⍀ 10k⍀
JP11
AD1852 STEREO DAC
DVDD AVDD
R9
1.96k⍀
220pF
U3B
R8
NP0
SSM2135
1.96k⍀
MCLK/SR SEL
C3
100nF
C2
100nF
R16
1.87k⍀
C14
1nF
NP0
R20
200⍀
J11
LEFT
OUT
DVDD
C15
10nF
NP0
C13
1nF
NP0
DVDD
AVDD
96/48
192/48
NC
R17
1.87k⍀
I/F MODE IDPM1 IDPM0
R4
10k⍀
R5
R10
1.96k⍀
C10
220pF
NP0
OUTL+
OUTL–
OUTR+
10k⍀
RJ, 16-BIT
0
0
1
1
0
1
0
1
R11
1.96k⍀
2
I S
3RD ORDER LP BESSEL FILTER
CORNER FREQUENCY: 75kHz
GROUP DELAY: ~3.5s
SDATA
LRCLK
SCLK
SDATA
LRCLK
RJ, 20-BIT
RJ, 24-BIT
U1
AD1852JRS
SCLK
MCLK
JP21
+AV
CC
C11
220pF
NP0
MCLK
R13
1.96k⍀
I/F
MODE
U3A
SSM2135
R12
1.96k⍀
C5
100nF
IDPM0
IDPM1
R18
1.87k⍀
C17
1nF
NP0
R21
200⍀
OUTR–
DEEMP
DEEMP
MUTE
J21
RIGHT
OUT
MUTE
C18
10nF
NP0
C16
1nF
NP0
C6
100nF
R19
1.87k⍀
CLATCH
CCLK
CLATCH
CCLK
R14
1.96k⍀
C12
220pF
NP0
R15
1.96k⍀
CDATA
CDATA
ZR
ZL
–AV
ZEROR
ZEROL
CC
FILTR
FILTB
AGND
C1
100nF
C7
10F
RESET
RESET
AGND
DGND
C8
10F
DGND
FB1
600Z
C4
100nF
CR1
ZERO
LEFT
CR2
ZERO
RIGHT
R6
221⍀
R7
221⍀
2
4
1
ZL
ZR
U2A
HC04
3
U2B
HC04
Figure 27. AD1852 DAC, Output Buffers, and LP Filters
REV. 0
–14–
AD1852
R5
3.01k⍀
R1
3.01k⍀
C2
270pF
L+
L–
SDATA
BCLK
SDATA
LRCLK
BCLK
R13
1.00k⍀
R2
3.01k⍀
L
L
2
0؇
I S LEFT/RIGHT
R17
DATA SEPARATOR
AND INVERTER
549⍀
1
0
C8
1.5nF
C7
1.5nF
LRCLK
AD797
AD1852
R+
R3
3.01k⍀
R14
1.00k⍀
180؇
R19
53.6k⍀
C5
2.2nF
R–
C2
270pF
R4
3.01k⍀
R6
3.01k⍀
R11
3.01k⍀
R7
3.01k⍀
C3
270pF
L+
L–
SDATA
LRCLK
BCLK
R
R
R8
3.01k⍀
R15
1.00k⍀
0؇
R18
549⍀
MCLK
1
0
C9
1.5nF
C10
1.5nF
AD797
AD1852
R+
R9
3.01k⍀
R16
1.00k⍀
180؇
R20
53.6k⍀
C6
2.2nF
R–
C4
270pF
R10
3.01k⍀
R12
3.01k⍀
LRCLK
2
I S INPUT TO
DATA SEPARATOR
Ln+1
Ln+2
Ln
Rn
Rn+1
Rn+2
SDATA
LRCLK
DATA SEPARATOR
OUTPUT
Ln
Rn
Ln+1
Rn+1
Ln+2
Rn+2
Ln
Rn
LSDATA
Ln+1
Rn+1
Ln+2
Rn+2
RDATA
Figure 28. Mono Application Circuit
REV. 0
–15–
AD1852
OUTLINE DIMENSIONS
Dimensions shown in inches and (mm).
28-Lead Shrink Small Outline Package (SSOP)
(RS-28)
0.407 (10.34)
0.397 (10.08)
28
15
14
0.311 (7.9)
0.212 (5.38)
0.205 (5.21)
0.301 (7.64)
1
0.07 (1.79)
0.078 (1.98)
0.068 (1.73)
PIN 1
0.066 (1.67)
0.03 (0.762)
8°
0°
0.0256
(0.65)
BSC
0.015 (0.38)
0.010 (0.25)
0.022 (0.558)
0.008 (0.203)
0.002 (0.050)
SEATING
PLANE
0.009 (0.229)
0.005 (0.127)
REV. 0
–16–
相关型号:
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