Stereo, 24-Bit, 96kHz
8X Oversampling Digital Interpolation Filter
49%
FPO
DF1704
TM
DESCRIPTION
The DF1704 is a high-performance, stereo, 8X oversampling
digital interpolation filter designed for high-end consumer
and professional audio applications. The DF1704 supports
24-bit, 96kHz operation and features user-programmable
functions, including selectable filter response, de-emphasis,
attenuation, and input/output data formats.
The DF1704 is the ideal companion for Texas Instruments'
PCM1704 24-bit audio digital-to-analog converter. This
combination allows for construction of very high-perfor-
mance audio systems and components.
FEATURES
q
COMPANION DIGITAL FILTER FOR THE PCM1704
24-BIT AUDIO DAC
q
HIGH PERFORMANCE FILTER:
Stopband Attenuation: 115dB
Passband Ripple:
0.00005dB
q
AUDIO INTERFACE:
Input Data Formats: Standard, Left-
Justified, and I
2
S
Input Word Length: 16, 20, or 24 Bits
Output Word Length: 16, 18, 20, or 24 Bits
Sampling Frequency: 32kHz to 96kHz
q
PROGRAMMABLE FUNCTIONS:
Hardware or Software Control Modes
Sharp or Slow Roll-Off Filter Response
Soft Mute
Digital De-Emphasis
Independent Left/Right Digital Attenuation
DF17
04
Serial
Input
I/F
Mode
Control
I/F
8X Oversampling
Digital Filter with
Function
Controller
Crystal/OSC
XTI
SCK
XTO
CLKO
(SF0) (SF1) (SRO)
V
DD
V
SS
Output I/F
BCKO
(I
2
S)
(IW1)
(IW0)
(OW1)
(OW0)
WCKO
DOL
DOR
MC/LRIP
MD/CKO
LRCIN
DIN
BCKIN
MODE
ML/RESV
(MUTE)
RST
(DEM)
Power Supply
SBAS099A MARCH 2001
www.ti.com
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright 1998, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
q
SYSTEM CLOCK: 256f
S
, 384f
S
, 512f
S
, 768f
S
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ON-CHIP CRYSTAL OSCILLATOR
q
+5V SINGLE-SUPPLY OPERATION
q
SMALL SSOP-28 PACKAGE
DF1704
2
SBAS099A
PIN
NAME
I/O
DESCRIPTION
1
DIN
IN
Serial Audio Data Input
(3)
2
BCKIN
IN
Bit Clock Input for Serial Audio Data
(3)
3
I
2
S
IN
Input Audio Data Format Selection
(2, 4)
4
IW0
IN
Input Audio Data Word Selection
(2, 4)
5
IW1
IN
Input Audio Data Word Selection
(2, 4)
6
XTI
IN
Oscillator Input /External Clock Input
7
XTO
OUT
Oscillator Output
8
V
SS
--
Digital Ground
9
CLKO
OUT
Buffered System Clock Output
10
MODE
IN
Mode Control Selection (H: Software, L: Hardware)
(1)
11
MD/CKO
IN
Control Data Input/Clock Output Frequency
Select
(1, 5)
12
MC/LRIP
IN
Control Data Clock/Polarity of LRCK Select
(1, 5)
13
ML/RESV
IN
Control Data Latch/Reserved
(1, 5)
14
RST
IN
Reset. When this pin is LOW, the digital filter
is held in reset.
(1)
15
MUTE
IN
Mute Control
(1, 4)
16
DEM
IN
De-Emphasis Control
(2, 4)
17
SF0
IN
Sampling Rate Select for De-emphasis
(2, 4)
18
SF1
IN
Sampling Rate Select for De-emphasis
(2, 4)
19
OW0
IN
Output Audio Data Word and Format Select
(2, 4)
20
OW1
IN
Output Audio Data Word and Format Select
(2, 4)
21
NC
--
No Connection
22
V
DD
--
Digital Power, +5V
23
DOR
OUT
Rch, Serial Audio Data Output
24
DOL
OUT
Lch, Serial Audio Data Output
25
WCKO
OUT
Word Clock for Serial Audio Data Output
26
BCKO
OUT
Bit Clock for Serial Audio Data Output
27
SRO
IN
Filter Response Select
(2, 4)
28
LRCIN
IN
L/R Clock Input (f
S
) for Serial Audio Data
(3)
NOTES: (1) Pins 10-15; Schmitt-Trigger input with pull-up resistor. (2) Pins
3-5, 16-20, 27; Schmitt-Trigger input with pull-down resister. (3) Pins 1, 2,
28; Schmitt-Trigger input. (4) Pins 3-5, 15-20, 27; these pins are invalid
when MODE (pin 10) is HIGH. (5) Pins 11-13; these pins have different
functions corresponding to MODE (pin 10), (HIGH/LOW).
PIN ASSIGNMENTS
PIN CONFIGURATION
ELECTROSTATIC
DISCHARGE SENSITIVITY
This integrated circuit can be damaged by ESD. Texas Instru-
ments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling
and installation procedures can cause damage.
ESD damage can range from subtle performance degradation
to complete device failure. Precision integrated circuits may
be more susceptible to damage because very small parametric
changes could cause the device not to meet its published
specifications.
Supply Voltage (V
DD
, V
CC
1, V
CC
2R, V
CC
2L) .................................... +6.5V
Supply Voltage Differences .................................................................
0.1
GND Voltage Differences ..................................................................
0.1V
Digital Input Voltage ................................................. 0.3V to (V
DD
+ 0.3V)
Input Current (any pins except power supplies) .............................
10mA
Power Dissipation .......................................................................... 300mW
Operating Temperature Range ......................................... 25
C to +85
C
Storage Temperature ...................................................... 55
C to +125
C
Lead Temperature (soldering, 5s) ................................................. +260
C
Package Temperature (reflow, 10s) .............................................. +235
C
ABSOLUTE MAXIMUM RATINGS
DIN
BCKIN
I
2
S
IW0
IW1
XTI
XTO
V
SS
CLKO
MODE
MD/CKO
MC/LRIP
ML/RESV
RST
LRCIN
SRO
BCKO
WCKO
DOL
DOR
V
DD
NC
OW1
OW0
SF1
SF0
DEM
MUTE
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
DF1704E
NC: No Connection
TOP VIEW
SSOP
PACKAGE
SPECIFIED
DRAWING
TEMPERATURE
PACKAGE
ORDERING
TRANSPORT
PRODUCT
PACKAGE
NUMBER
RANGE
MARKING
NUMBER
MEDIA
DF1704E
SSOP-28
324
25
C to +85
C
DF1704E
DF1704E
Rails
PACKAGE/ORDERING INFORMATION
DF1704
3
SBAS099A
ELECTRICAL CHARACTERISTICS
All specifications at +25
C, V
DD
= +5V, unless otherwise noted.
DF1704E
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
RESOLUTION
24
Bits
INPUT DATA FORMAT
Audio Data Interface Format
Standard /Left-Justified /I
2
S
Audio Data Bit Length
16/20/24 Selectable
Audio Data Format
MSB-First, Two's Binary Comp
Sampling Frequency (f
S
)
32
96
kHz
System Clock Frequency
256/384/512/ 768f
S
OUTPUT DATA FORMAT
Audio Data Interface Format
Right-Justified
Audio Data Bit Length
16/20/24 Selectable
Audio Data Format
MSB-First, Binary Two's Complement
DIGITAL INPUT/OUTPUT
Input Logic Level:
V
IH
2.0
V
V
IL
0.8
V
Output Logic Level: V
OH
I
OH
= 2mA
4.5
V
V
OL
I
OL
= 4mA
0.5
V
CLKO AC CHARACTERISTICS
Rise Time (t
R
)
20% to 80% V
DD
, 10pF
4
ns
Fall Time
(t
F
)
80% to 20% V
DD
, 10pF
3
ns
Duty Cycle
10pF Load
37
%
DIGITAL FILTER PERFORMANCE
Filter Characteristics 1 (Sharp Roll-Off)
Passband
0.00005dB
0.454f
S
3dB
0.493f
S
Stopband
0.546f
S
Passband Ripple
0.00005
dB
Stopband Attenuation
Stopband = 0.546f
S
115
dB
Filter Characteristics 2 (Sharp Roll-Off)
Passband Ripple
0.0001dB
0.254f
S
3dB
0.460f
S
Stopband
0.732f
S
Passband Ripple
0.0001
dB
Stopband Attenuation
Stopband = 0.748f
S
100
dB
Delay Time
45.125/f
S
sec
De-Emphasis Error
0.003
dB
POWER SUPPLY REQUIREMENTS
Voltage Range
V
DD
4.5
5
5.5
VDC
Supply Current: I
DD
20
30
mA
Power Dissipation
100
150
mW
TEMPERATURE RANGE
Operation
25
+85
C
Storage
55
+100
C
DF1704
4
SBAS099A
TYPICAL CHARACTERISTICS OF INTERNAL FILTER
DIGITAL FILTER (DE-EMPHASIS OFF, f
S
= 44.1kHz)
DE-EMPHASIS AND DE-EMPHASIS ERROR
0
4
3.5
3
2.5
2
1.5
1
0.5
Frequency (f
S
)
20
0
20
40
60
80
100
120
140
160
180
200
FREQUENCY RESPONSE (Sharp Roll Off)
Attenuation (dB)
0
0.5
0.45
0.4
0.3
0.35
0.25
0.2
0.15
0.1
0.5
Frequency (f
S
)
0.0001
0.00008
0.00006
0.00004
0.00002
0
0.00002
0.00004
0.00006
0.00008
0.0001
PASSBAND RIPPLE (Sharp Roll Off)
Attenuation (dB)
0
4
3.5
3
2.5
2
1.5
1
0.5
Frequency (f
S
)
0
20
40
60
80
100
120
140
160
180
200
FREQUENCY RESPONSE (Slow Roll Off)
Attenuation (dB)
0
0.1
0.2
0.3
0.4
0.5
0.7
0.6
Frequency (f
S
)
TRANSITION CHARACTERISTIC (Slow Roll Off)
0
5
10
15
Attenuation (dB)
0
14
12
10
8
6
4
2
Frequency ( f
S
)
0
2
4
6
8
10
DE-EMPHASIS (f
S
= 32kHz)
Level (dB)
0
14
12
8
10
6
4
2
Frequency (f
S
)
0.01
0.008
0.006
0.004
0.002
0
0.002
0.004
0.006
0.008
0.01
DE-EMPHASIS ERROR (f
S
= 32kHz)
Error (dB)
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