TI PCM1730E/2K

PCM1730
SLES021 – NOVEMBER 2001
24-BIT, 192-kHz SAMPLING ADVANCED SEGMENT, AUDIO
STEREO DIGITAL-TO-ANALOG CONVERTER
FEATURES
D 24-Bit Resolution
D Analog Performance (VCC = 5 V):
D
D
D
D
D
D
D
D
D
D
D
D
– Dynamic Range: 117 dB (Typically)
– SNR: 117 dB (Typically)
– THD+N: 0.0004% (Typically)
– Full-Scale Output (At Post Amp): 2.2-Vrms
Differential Current Output: ±2.48 mA
8× Oversampling Digital Filter:
– Stop-Band Attenuation: –82 dB
– Pass-Band Ripple: ±0.002 dB
Sampling Frequency of 10 kHz to 200 kHz
System Clock: 128, 192, 256, 384, 512, or
768 fS With Auto Detect
Accepts 16-, 20-, and 24-Bit Audio Data
Data Formats: Standard, I2S, and
Left-Justified
Digital De-Emphasis
Soft Mute
Zero Flags for Each Output
Dual Supply Operation:
– 5 V for Analog
– 3.3 V for Digital
5-V Tolerant Digital Inputs
Small 28-Lead SSOP Package
APPLICATIONS
D A/V Receivers
D DVD Movie Players
D SACD Player
D HDTV Receivers
D Car Audio Systems
D Digital Multi-Track Recorders
D Other Applications Requiring 24-Bit Audio
DESCRIPTION
The PCM1730 is a CMOS, monolithic integrated circuit
that includes stereo digital-to-analog converters and
support circuitry in a small 28-lead SSOP package. The
data converters utilize Texas Instruments’ advanced
segment DAC architecture to achieve excellent
dynamic performance and improved tolerance to clock
jitter. The PCM1730 provides balanced current outputs,
allowing the user to optimize analog performance
externally. Sampling rates up to 200 kHz are supported.
PACKAGE/ORDERING INFORMATION
PRODUCT
PACKAGE
PACKAGE
DRAWING
NUMBER
OPERATING
TEMPERATURE RANGE
PACKAGE
MARKING
PCM1730E
28 Lead SSOP
28-Lead
28DB
–25°C
25°C to 85°C
PCM1730E
ORDERING NUMBER†
PCM1730E
PCM1730E/2K
† Models with a slash (/) are available only in tape and reel in the quantities indicated (e.g., /2K indicates 2000
devices per reel). Ordering 2000 pieces of PCM1730E/2K will get a single 2000-piece tape and reel.
This integrated circuit can be damaged by ESD. Texas Instruments 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.
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.
Copyright  2001, Texas Instruments Incorporated
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.
www.ti.com
1
PCM1730
SLES021 – NOVEMBER 2001
pin assignments
SSOP PACKAGE
(TOP VIEW)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
RST
ZEROL
ZEROR
LRCK
DATA
BCK
SCKI
DGND
VDD
DEMP0
DEMP1
FMT0
FMT1
FMT2
28
27
26
25
24
23
22
21
20
19
18
17
16
15
VCC3
AGND2
IOUTL–
IOUTL+
VCC2
VCC1
VCOM3
IREF
VCOM2
VCOM1
AGND1
IOUTR+
IOUTR–
MUTE
functional block diagram
IOUTL+
LRCK
DATA
BCK
Current
Segment
DAC
Serial
Input
I/F
IOUTL–
VCOM2
RST
Advanced
Segment
DAC
Modulator
Digital
Filter
MUTE
FMT0
FMT1
FMT2
IREF
Bias
and
Vref
I/V and Filter
VCOM1
VCOM3
Function
Control
I/F
IOUTR–
DEMP0
DEMP1
Current
Segment
DAC
IOUTR+
System Clock
I/V and Filter
2
www.ti.com
AGND2
VCC3
AGND1
VCC2
VCC1
Power Supply
DGND
ZEROL
Manager
Zero Detect
VDD
System Clock
ZEROR
SCKI
PCM1730
SLES021 – NOVEMBER 2001
Terminal Functions
TERMINAL
NAME
PIN
I/O
DESCRIPTION
AGND1
18
–
Analog ground
AGND2
27
–
BCK
6
I
Analog ground
Bit clock input†
DATA
5
I
DEMP0
10
I
Serial audio data input†
De-emphasis control‡
DEMP1
11
I
De-emphasis control‡
DGND
8
–
Digital ground
FMT0
12
I
FMT1
13
I
Audio data format select†
Audio data format select†
FMT2
14
I
Audio data format select†
IOUTL–
IOUTL+
26
O
L-channel analog current output –
25
O
L-channel analog current output +
IOUTR–
IOUTR+
16
O
R-channel analog current output –
17
O
R-channel analog current output +
IREF
LRCK
21
–
4
I
Output current reference bias pin. Connect a 16-kΩ resistor to GND.
Left and right clock (fS)†
MUTE
15
I
RST
1
I
Analog output mute control†
Reset†
SCKI
7
I
System clock input†
VCC1
VCC2
23
–
Analog supply, 5 V
24
–
Analog supply, 5 V
VCC3
VCOM1
28
–
Analog power supply, 5 V
19
–
Internal bias decoupling pin
VCOM2
VCOM3
20
–
Common voltage for I/V
22
–
Internal bias decoupling pin
VDD
ZEROL
9
–
Digital supply, 3.3 V
2
O
Zero flag for L-channel
ZEROR
3
O
Zero flag for R-channel
† Schmitt-trigger input, 5-V tolerant
‡ Schmitt-trigger input with internal pulldown, 5-V tolerant
www.ti.com
3
PCM1730
SLES021 – NOVEMBER 2001
absolute maximum ratings over operating free-air temperature (unless otherwise noted)†
Supply voltage: VCC1, VCC2, VCC3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.5 V
Supply voltage: VDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 V
Supply voltage differences: VCC1, VCC2, and VCC3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.1 V
Ground voltage differences: AGND1, AGND2, and DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±0.1 V
Digital input voltage: LRCK, DATA, BCK, SCKI, DEMP0, DEMP1, FMT0, FMT1,
FMT2, RST, and MUTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to 6.5 V
Digital input voltage: ZEROL, ZEROR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to (VDD + 0.3 V)
Analog input voltage: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to (VCC + 0.3 V)
Input current (any pins except supplies) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±10 mA
Ambient temperature under bias, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –40°C to 125°C
Storage temperature, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –55°C to 150°C
Junction temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Lead temperature (soldering) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C, 5 s
Package temperature (IR reflow, peak) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235°C, 10 s
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
electrical characteristics, all specifications at TA = 25°C, VCC = 5 V, VDD = 3.3 V, fS = 44.1 kHz, system
clock = 256 fS and 24-bit data (unless otherwise noted)
PCM1730E
PARAMETER
TEST CONDITIONS
MIN
TYP
RESOLUTION
MAX
24
UNIT
Bits
DATA FORMAT
Standard, I2S, left justified
Audio data interface format
fS
Audio data bit length
16, 20, 24-bits selectable
Audio data format
MSB first, 2’s complement
Sampling frequency
10
System clock frequency
200
kHz
128, 192, 256, 384, 512, 768 fS
DIGITAL INPUT/OUTPUT
Logic family
VIH
VIL
TTL compatible
High-level input logic level
2
0.8
IIH
IIL
Input logic current (see Note 1)
VIN = VDD
VIN = 0 V
IIH
IIL
Input logic current (see Note 2)
VIN = VDD
VIN = 0 V
VOH
VOL
High-level output logic level
Low-level output logic level
10
–10
65
100
–10
IOH = –2 mA
IOL = 2 mA
2.4
www.ti.com
VDC
µA
A
µA
A
VDC
1
NOTES: 1. Pins 1, 4, 5, 6, 7, 12, 13, 14, and 15: RST, LRCK, DATA, BCK, SCKI, FMT0, FMT1, FMT2, and MUTE
2. Pins 10 and 11: DEMP0, DEMP1
4
VDC
Low-level input logic level
VDC
PCM1730
SLES021 – NOVEMBER 2001
electrical characteristics, all specifications at TA = 25°C, VCC = 5 V, VDD = 3.3 V, fS = 44.1 kHz, system
clock = 256 fS and 24-bit data (unless otherwise noted) (continued)
PCM1730E
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
0.0004%
0.008%
UNIT
DYNAMIC PERFORMANCE (see Note 3)
THD+N
Total
T
t l harmonic
h
i distortion
di t ti plus
l
noise
fS = 44.1 kHz
fS = 96 kHz
VOUT = 0 dB
0.0006%
fS = 192 kHz
EIAJ, A-weighted, fS = 44.1 kHz
Dynamic range
0.0012%
114
EIAJ, A-weighted, fS = 96 kHz
Signal-to-noise
Signal
to noise ratio
114
EIAJ, A-weighted, fS = 96 kHz
Channel se
separation
aration
Level linearity error
fS = 192 kHz
VOUT = –110 dB
117
dB
117
EIAJ, A-weighted, fS = 192 kHz
fS = 44.1 kHz
fS = 96 kHz
dB
117
EIAJ, A-weighted, fS = 192 kHz
EIAJ, A-weighted, fS = 44.1 kHz
117
110
115
113
dB
111
±1
dB
DC ACCURACY
VCOM2 voltage
VCOM2 output current
Delta VCOM2 < 5%
Gain error
Gain mismatch, channel-tochannel
Bipolar zero error
At BPZ
2.45
V
100
µA
±2
%/FSR
±0.5
%/FSR
±0.5
%/FSR
±2.48
mAp-p
mAp-p
ANALOG OUTPUT
Output current
Full scale (–0 dB)
Center current
BPZ input
0
DIGITAL FILTER PERFORMANCE—FILTER CHARACTERISTICS
Pass band
±0.002 dB
0.454 fS
–3 dB
0.49 fS
Stop band
0.546 fS
Pass-band ripple
Stop band attenuation
Stop-band
±0.002
–75
Stop band = 0.546 fS
Stop band = 0.567 fS
Delay time
dB
–82
dB
29/fS
s
±0.1
De-emphasis error
dB
dB
NOTE 3: Analog performance specifications are measured by audio precision II under averaging mode. At 44.1-kHz operation, measurement
bandwidth is limited to 20 kHz. At 96-kHz and 192-kHz operation, measurement bandwidth is limited to 40 kHz.
www.ti.com
5
PCM1730
SLES021 – NOVEMBER 2001
electrical characteristics, all specifications at TA = 25°C, VCC = 5 V, VDD = 3.3 V, fS = 44.1 kHz, system
clock = 256 fS and 24-bit data (unless otherwise noted)(continued)
PCM1730E
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
3
3.3
3.6
4.75
5
5.25
7
9.8
UNIT
POWER SUPPLY REQUIREMENTS
VDD
VCC
Voltage range
fS = 44.1 kHz
fS = 96 kHz
IDD
Supply current
ICC
PD
Power dissi
dissipation
ation
VDC
15
fS = 192 kHz
fS = 44.1 kHz
30
fS = 96 kHz
fS = 192 kHz
34.5
fS = 44.1 kHz
fS = 96 kHz
188
fS = 192 kHz
282
33
46.2
mA
36.5
263
222
mW
TEMPERATURE RANGE
Operation temperature
θJA
Thermal resistance
–25
28-pin SSOP
85
°C
°C/W
100
functional description
system clock and reset functions
The PCM1730 requires a system clock for operating the digital interpolation filters and advanced segment DAC
modulators. The system clock is applied at the SCKI input (pin 7). The PCM1730 has a system clock detection
circuit, which automatically senses if the system clock is operating at 128 fS to 768 fS. Table 1 shows examples
of system clock frequencies for common audio sampling rates.
Figure 1 shows the timing requirements for the system clock input. For optimal performance, it is important to
use a clock source with low phase jitter and noise. Texas Instruments’ PLL1700 multi-clock generator is an
excellent choice for providing the PCM1730 system clock.
tw(SCKH)
2V
System Clock
0.8 V
tw(SCKL)
System Clock
Pulse Cycle Time
PARAMETER
MIN
UNIT
System clock pulse width high, tw(SCKH)
5
ns
System clock pulse width high, tw(SCKL)
5
ns
Figure 1. System Clock Input Timing
6
www.ti.com
PCM1730
SLES021 – NOVEMBER 2001
system clock and reset functions (continued)
Table 1. System Clock Rates for Common Audio Sampling Frequencies
SAMPLING FREQUENCY
SYSTEM CLOCK FREQUENCY (fSCLK) (MHz)
128 fS
192 fS
256 fS
32 kHz
4.096
6.144
8.192
384 fS
12.288
512 fS
16.384
768 fS
24.576
44.1 kHz
5.6488
8.4672
11.2896
16.9344
22.5792
33.8688
48 kHz
6.144
9.216
12.288
18.432
24.576
36.864
96 kHz
12.288
18.432
24.576
36.864
49.152
73.728
192 kHz
24.576
36.864
49.152
73.728
See Note 4
See Note 4
NOTE 4: This system clock rate is not supported for the given sampling frequency.
power-on and external reset functions
The PCM1730 includes a power-on reset function. Figure 2 shows the operation of this function. The system
clock input at SCKI should be active for at least one clock period prior to VDD = 2 V. With the system clock active
and VDD > 2 V, the power-on reset function will be enabled. The initialization sequence requires 1024 system
clocks from the time VDD > 2 V. The PCM1730 also includes an external reset capability using the RST input
(pin 1). This allows an external controller or master reset circuit to force the PCM1730 to initialize to its reset
state. Figure 3 shows the external reset operation and timing. The RST pin is set to logic 0 for a minimum of
20 ns. The RST pin is then set to a logic 1 state, which starts the initialization sequence, which requires 1024
system clock periods. The external reset is especially useful in applications where there is a delay between
PCM1730 power up and system clock activation. In this case, the RST pin should be held at a logic 0 level until
the system clock has been activated. The RST pin may then be set to logic 1 state to start the initialization
sequence.
www.ti.com
7
PCM1730
SLES021 – NOVEMBER 2001
functional description (continued)
VDD
2.4 V (Max)
2 V (Typ)
1.6 V (Min)
Reset
Reset Removal
Internal Reset
1024 System Clocks
System Clock
Figure 2. Power-On Reset Timing
RST (Pin 36)
50% of VDD
t(RST)
Reset
Reset Removal
Internal Reset
1024 System Clocks
System Clock
PARAMETER
Reset pulse width low, t(RST)
MIN
20
UNIT
ns
Figure 3. External Reset Timing
audio data interface
audio serial interface
The audio serial interface for the PCM1730 is comprised of a 3-wire synchronous serial port. It includes LRCK
(pin 4), BCK (pin 6), and DATA (pin 5). BCK is the serial audio bit clock, and it is used to clock the serial data
present on DATA into the audio interface’s serial shift register. Serial data is clocked into the PCM1730 on the
rising edge of BCK. LRCK is the serial audio left/right word clock. It is used to latch serial data into the serial
audio interface’s internal registers.
LRCK should be synchronous with the system clock. In the event these clocks are not synchronized, the
PCM1730 can compensate for the phase difference internally. If the phase difference between LRCK and SCKI
is greater than 6-bit clocks (BCK), the synchronization is performed internally. While the synchronization is
processing, the analog output is forced to bipolar zero level. The synchronization typically occurs in less than
one cycle of LRCK.
Ideally, it is recommended that LRCK and BCK be derived from the system clock input or output, SCKI or SCKO.
The left/right clock, LRCK, is operated at the sampling frequency, fS.
8
www.ti.com
PCM1730
SLES021 – NOVEMBER 2001
audio data formats and timing
The PCM1730 supports industry-standard audio data formats, including standard right-justified, I2S, and
left-justified. The data formats are shown in Figure 4. Data formats are selected by using the FMT2 (pin 14),
FMT1 (pin 13) and FMT0 (pin 12) as shown in Table 2. All formats require binary 2’s complement, MSB-first
audio data. Figure 5 shows a detailed timing diagram for the serial audio interface.
Table 2. Audio Data Format Select
FMT2
(PIN 14)
FMT1
(PIN 13)
FMT0
(PIN 12)
Low
Low
Low
16-bit standard format, right-justified
Low
Low
High
20-bit standard format, right-justified
Low
High
Low
24-bit standard format, right-justified
FORMAT
Low
High
High
High
Low
Low
24-bit MSB-first, left-justified format
16-bit I2S format
High
Low
High
24-bit I2S format
High
High
Low
Reserved
High
High
High
Reserved
zero detect
When the PCM1730 detects that the audio input data in L-channel or R-channel is continuously zero for 1024
fS, the PCM1730 sets ZEROL (pin 2) or ZEROR (pin 3) to high.
soft mute
The PCM1730 supports mute operation. When MUTE (pin 15) is set to HIGH, both analog outputs are turned
to bipolar zero levels by –0.5-dB steps with transition speed of 1/fS per step. This system provides pop-free
muting of DAC output.
de-emphasis
The PCM1730 supports de-emphasis filter performance for sampling frequency 32 kHz, 44.1 kHz, 48 kHz.
Sampling frequency is selectable by using DEMP1 (pin 11) DEMP0 (pin 10) as shown in Table 3.
Table 3. De-Emphasis Control
DEMP1 (PIN 11)
DEMP0(PIN 10)
DE-EMPHASIS FUNCTION
Low
Low
Disabled
Low
High
48 kHz
High
Low
44.1 kHz
High
High
32 kHz
www.ti.com
9
PCM1730
SLES021 – NOVEMBER 2001
functional description (continued)
(1) Standard Data Format (Right Justified); L-channel = High, R-channel = Low
1/fS
LRCK
R-Channel
L-Channel
BCK
Audio Data Word = 16 Bit
DATA
14 15 16
1
2
MSB
15 16
1
2
15 16
LSB
Audio Data Word = 20 Bit
DATA
18 19 20
1
2
19 20
1
2
19 20
LSB
MSB
Audio Data Word = 24 Bit
DATA
22 23 24
1
2
23 24
MSB
1
2
23 24
LSB
(2) Left Justified Data Format: L-channel = High, R-channel = Low
1/fS
LRCK
R-Channel
L-Channel
BCK
Audio Data Word = 24 Bit
DATA
1
2
23 24
1
2
23 24
1
2
LSB
MSB
(3) I2S Data Format: L-channel = Low, R-channel = High
1/fS
LRCK
L-Channel
R-Channel
BCK
Audio Data Word = 16 Bit
DATA
1
2
MSB
15 16
1
2
1
2
15 16
1
2
1
2
LSB
Audio Data Word = 24 Bit
DATA
1
2
MSB
23 24
LSB
Figure 4. Audio Data Input Formats
10
www.ti.com
23 24
PCM1730
SLES021 – NOVEMBER 2001
functional description (continued)
50% of VDD
LRCK
t(BCH)
t(BCL)
t(LB)
50% of VDD
BCK
t(BL)
t(BCY)
50% of VDD
DATA
tsu
th
PARAMETER
MIN
UNIT
BCK pulse cycle time, t(BCY)
70
ns
BCK pulse width low, tw(BCL)
30
ns
BCK pulse width high, tw(BCH)
30
ns
BCK rising edge to LRCK edge, t(BL)
10
ns
LRCK edge to BCK rising edge, t(LB)
10
ns
DATA set up time, tsu
10
ns
DATA hold time, th
10
ns
50% ±2 bit clock
LRCK clock duty
Figure 5. Audio Interface Timing
www.ti.com
11
PCM1730
SLES021 – NOVEMBER 2001
typical connection diagram
5V
15 V
–15 V
Controller
1
RST
2
VCC3
28
ZEROL
AGND2
27
3
ZEROR
IOUTL–
26
–
L/R Clock (fS)
4
LRCK
IOUTL+
25
+
Audio DATA
5
DATA
VCC2
24
+
Bit Clock
6
BCK
VCC1
23
System Clock
7
SCKI
VCOM3
22
IREF
21
VCOM2
20
10 DEMP0
VCOM1
19
11 DEMP1
AGND1
18
12 FMT0
IOUTR+
17
13 FMT1
IOUTR–
16
–
14 FMT2
MUTE
15
+
3.3 V
+
8
DGND
9
VDD
PCM1730E
+
–
+
+
–
+
–
+
+
–
Analog Output Stage
NOTE: Regarding R/C values for analog output stage, see Figure 9.
Figure 6. Typical Application Circuit for Standard PCM Audio Operation
12
VOUT
L-Channel
www.ti.com
VOUT
R-Channel
PCM1730
SLES021 – NOVEMBER 2001
analog outputs
5V
VCC3
PCM1730E
28
AGND2
27
IOUTL–
26
IOUTL+
25
VCC2
24
VCC1
23
VCOM3
22
IREF
21
VCOM2
20
VCOM1
19
AGND1
18
IOUTR+
17
IOUTR–
16
MUTE
C13
0.1 µF
R15
+
R11
10 µF
–
C11
R13
+
+
R16
C15
R14
–
+
VOUT
L-Channel
R17
–
+
10 µF
R1
16 kΩ
C17
10 µF
+
C12
R18
C16
R12
C14
10 µF
+
C23
R25
R21
–
C21
15
C27
R23
+
+
R26
C25
R24
–
+
VOUT
R-Channel
R27
–
C22
R28
C26
R22
C24
NOTE: Example R/C values for fC 45 kHz
R11–R18, R21–R28: 620 Ω, C11, C12, C21, C22: not populated, C13, C14, C23, C24: 5600 pF, C15, C25: 8200 pF, C16, C17, C26,
C27: 1800 pF
Figure 7. Typical Application for Analog Output Stage
analog output level and I/V converter
The signal level of DAC current output pins (IOUTL+, IOUTL–, IOUTR+, IOUTR–) is ±2.48 mAp-p at 0 dB (full scale).
The voltage output of the I/V converter is given by following equation:
VOUT = ±2.48 mAp–p × Rf
Here, Rf is the feedback resistor in the I/V conversion circuit, R11, R12, R21, R22 on typical application circuit.
The common level of the I/V conversion circuit must be same as common level of DAC IOUT which is given by
VCOM2 reference voltage, which is 2.48 V dc typically. The noninverting inputs of the op amps shown in the I/V
circuits are connected to VCOM2 to provide the common bias voltage.
www.ti.com
13
PCM1730
SLES021 – NOVEMBER 2001
op amp for I/V converter circuit
OPA627BP/BM or NE5534 type op amp is recommended for I/V conversion circuit to obtain specified audio
performance. Dynamic performance such as gain bandwidth, settling time and slew rate of op amp gives audio
dynamic performance at I/V section. Input noise specification of op amp should be considered to obtain 120 dB
S/N ratio.
analog gain by balanced amp
The I/V converters are followed by balanced amplifier stages, which sum the differential signals for each
channel, creating a single-ended voltage output. In addition, the balanced amplifiers provide a second-order
low pass filter function, which band limits the audio output signal. The cutoff frequency and gain are given by
the external R and C component values. In this case, the cutoff frequency is 45 kHz with a gain of 1. The output
voltage for each channel is 6.2 Vp-p, or 2.2 Vrms.
reference current resistor
As shown in the analog output application circuit, there is a resistor connected from IREF (pin 21) to analog
ground, designated as R1. This resistor sets the current for the internal reference circuit. The value of R1 must
be 16 kΩ ±1% in order to match the specified gain error shown in the specifications table.
theory of operation
Upper
6 Bit
ICOB
Decoder
0–62
Level
0–66
Advanced
DWA
Digital Input
24 Bit
8 fS
MSB
and
Lower 18 Bit
3rd-Order
5-Level
Sigma-Delta
Current
Segment
DAC
Analog Output
0–4
Level
Figure 8. Advanced Segments DAC
The PCM1730 utilizes Texas Instruments’ newly developed advanced segment DAC architecture to achieve
excellent dynamic performance and improved tolerance to clock jitter. The PCM1730 provides balanced current
outputs, allowing the user to optimize analog performance externally.
Digital input data via digital filter separates into the upper 6 bits and lower the 18 bits. The upper 6 bits are
converted to ICOB (inverted complementary offset binary) code. The lower 18 bits associated with the MSB are
processed by five level third order delta-sigma modulator operated at 64 fS. The one level of the modulator is
equivalent to the 1 LSB of the above code converter. The data groups processed in the ICOB converter and
third order delta-sigma modulator are summed together to be created over the 64 level digital code, and then
processed in DWA (data weighted averaging) to reduce noise produced by element mismatch. The data of over
64 level via DWA is converted to analog output in the differential current segment portion.
This architecture has overcome the various drawbacks of conventional multi-bit and also achieves excellent
dynamic performance.
considerations for application circuit
PCB layout guidelines
A typical PCB floor plan for the PCM1730 is shown in Figure 9. A ground plane is recommended, with the analog
and digital sections being isolated from one another using a split or cut in the circuit board. The PCM1730 should
be oriented with the digital I/O pins facing the ground plane split/cut to allow for short, direct connections to the
digital audio interface and control signals originating from the digital section of the board.
14
www.ti.com
PCM1730
SLES021 – NOVEMBER 2001
PCB layout guidelines (continued)
Separate power supplies are recommended for the digital and analog sections of the board. This prevents the
switching noise present on the digital supply from contaminating the analog power supply and degrading the
dynamic performance of the D/A converters. In cases where a common 5-V supply must be used for the analog
and digital sections, an inductance (RF choke, ferrite bead) should be placed between the analog and digital
5-V supply connections to avoid coupling of the digital switching noise into the analog circuitry. Figure 10 shows
the recommended approach for single-supply applications.
bypass and decoupling capacitor requirements
Various-sized decoupling capacitors can be used, with no special tolerances being required. All capacitors
should be located as close to the appropriate pins of the PCM1730 as possible to reduce noise pickup from
surrounding circuitry. Aluminum electrolytic capacitors that are designed for hi-fi audio applications are
recommended for larger values, while metal-film or monolithic ceramic capacitors are used for smaller values.
I/V section
I/V conversion circuit by op amp IC and feedback resistor should achieve excellent performance of the
PCM1730. To obtain 0.0004% THD+N, 117-dB signal-to-noise ratio audio performance, THD+N and input noise
performance by the op amp IC should be considered, especially if the input noise of the op amp directly gives
output noise level of the application. The IOUT– pin on the PCM1730 and the inverted input on the I/V amp should
be connected as short distance.
post LPF design
Out-band noise level and attenuated sampling spectrum level are much lower than typical delta-sigma type DAC
due to the combination of a high-performance digital filter and advanced segment DAC architecture. Secondorder or third-order post LPF is recommended as post LPF of the PCM1730. Cutoff frequency of post LPF is
depends on applications to that there are many sampling rate operation such as fS = 44.1 kHz on CDDA,
fS = 96 kHz on DVD–M, fS = 192 kHz on DVD–A.
Digital Power
+VD
DGND
Analog Power
AGND +5VA
+VS –VS
REG
VCC
Digital
Logic
and
Audio
Processor
VDD
DGND
Output
Circuits
PCM1730
Digital
Ground
AGND
Digital Section
Analog Section
Analog
Ground
Return Path for Digital Signals
Figure 9. Recommended PCB Layout
www.ti.com
15
PCM1730
SLES021 – NOVEMBER 2001
Power Supplies
RF Choke or Ferrite Bead
5V
AGND
+VS –VS
REG
VCC
VDD
VDD
DGND
PCM1730
Output
Circuits
Digital
Ground
AGND
Digital Section
Analog Section
Figure 10. Single-Supply PCB Layout
16
www.ti.com
Common
Ground
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
digital filter
de-emphasis off
AMPLITUDE
vs
FREQUENCY
AMPLITUDE
vs
FREQUENCY
0
3
0.003
VCC = 5 V
VDD = 3.3 V
TA = 25°C
–20
2
0.002
VCC = 5 V
VDD = 3.3 V
TA = 25°C
–60
Amplitude – dB
Amplitude – dB
–40
–80
–100
1
0.001
0
–1
–0.001
–120
–2
–0.002
–140
–160
0
1
2
3
4
–3
–0.003
0.0
Frequency [x fs]
0.1
0.2
0.3
0.4
0.5
Frequency [x fs]
Figure 11
Figure 12
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
www.ti.com
17
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
de-emphasis error
DE-EMPHASIS LEVEL
vs
FREQUENCY
DE-EMPHASIS ERROR
vs
FREQUENCY
0
0.5
VCC = 5 V
VDD = 3.3 V
fS = 32 kHz
TA = 25°C
–1
0.3
De-emphasis Error – dB
De-emphasis Level – dB
–2
VCC = 5 V
VDD = 3.3 V
fS = 32 kHz
TA = 25°C
0.4
–3
–4
–5
–6
–7
0.2
0.1
–0.0
–0.1
–0.2
–8
–0.3
–9
–0.4
–10
–0.5
0
2
4
6
8
10
12
14
0
2
4
f – Frequency – kHz
6
10
12
DE-EMPHASIS LEVEL
vs
FREQUENCY
DE-EMPHASIS ERROR
vs
FREQUENCY
0
0.5
VCC = 5 V
VDD = 3.3 V
fS = 44.1 kHz
TA = 25°C
–1
VCC = 5 V
VDD = 3.3 V
fS = 44.1 kHz
TA = 25°C
0.4
0.3
De-emphasis Error – dB
–2
–3
–4
–5
–6
–7
0.2
0.1
–0.0
–0.1
–0.2
–8
–0.3
–9
–0.4
–10
–0.5
0
2
4
6
8
10
12
14
16
18
20
f – Frequency – kHz
0
2
4
6
8
10
12
14
16
18
f – Frequency – kHz
Figure 15
Figure 16
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
18
14
Figure 14
Figure 13
De-emphasis Level – dB
8
f – Frequency – kHz
www.ti.com
20
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
de-emphasis error (continued)
DE-EMPHASIS ERROR
vs
FREQUENCY
DE-EMPHASIS LEVEL
vs
FREQUENCY
0.5
0
VCC = 5 V
VDD = 3.3 V
fs = 48 kHz
TA = 25°C
De-emphasis Level – dB
–2
VCC = 5 V
VDD = 3.3 V
fS = 48 kHz
TA = 25°C
0.4
0.3
De-emphasis Error – dB
–1
–3
–4
–5
–6
–7
0.2
0.1
–0.0
–0.1
–0.2
–0.3
–8
–0.4
–9
–0.5
–10
0
2
4
6
8
10
12
14
16
18
20
0
22
2
4
6
8
10
12
14
16
18
20
22
f – Frequency – kHz
f – Frequency – kHz
Figure 17
Figure 18
analog dynamic performance
TOTAL HARMONIC DISTORTION + NOISE
vs
SUPPLY VOLTAGE
TOTAL HARMONIC DISTORTION + NOISE
vs
FREE-AIR TEMPERATURE
0.20
0.0020
THD+N – Total Harmonic Distortion + Noise – %
THD+N – Total Harmonic Distortion + Noise – %
0.20
0.0020
VDD = 3.3 V
TA = 25°C
0.15
0.0015
0.10
0.0010
fS = 96 kHz
0.05
0.0005
fS = 44.1 kHz
0.00
0.0000
4.50
4.75
5.00
5.25
5.50
VCC = 5 V
VDD = 3.3 V
0.15
0.0015
0.10
0.0010
fS = 96 kHz
0.05
0.0005
fS = 44.1 kHz
0.00
0.0000
–50
–25
0
25
50
75
100
TA – Free-Air Temperature – °C
VCC – Supply Voltage – V
Figure 20
Figure 19
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
www.ti.com
19
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
analog dynamic performance (continued)
DYNAMIC RANGE
vs
SUPPLY VOLTAGE
DYNAMIC RANGE
vs
FREE-AIR TEMPERATURE
120
120
VDD = 3.3 V
TA = 25°C
VCC = 5 V
VDD = 3.3 V
119
Dynamic Range – dB
Dynamic Range – dB
119
fS = 96 kHz
118
fS = 44.1 kHz
117
116
4.50
fS = 44.1 kHz
118
fS = 96 kHz
117
4.75
5.00
5.25
116
–50
5.50
–25
0
Figure 21
75
100
SNR
vs
FREE-AIR TEMPERATURE
120
120
VCC = 5 V
VDD = 3.3 V
TA = 25°C
VCC = 5 V
VDD = 3.3 V
119
119
118
SNR – dB
SNR – dB
50
Figure 22
SNR
vs
SUPPLY VOLTAGE
fS = 44.1 kHz
fS = 96 kHz
117
116
4.50
25
TA – Free-Air Temperature – °C
VCC – Supply Voltage – V
4.75
5.00
118
fS = 44.1 kHz
fS = 96 kHz
117
5.25
5.50
116
–50
–25
0
25
50
75
100
TA – Free-Air Temperature – °C
VCC – Supply Voltage – V
Figure 23
Figure 24
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
20
www.ti.com
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
analog dynamic performance (continued)
CHANNEL SEPARATION
vs
SUPPLY VOLTAGE
CHANNEL SEPARATION
vs
FREE-AIR TEMPERATURE
118
117
116
Channel Separation – dB
Channel Separation – dB
117
118
VDD = 3.3 V
TA = 25°C
fS = 44.1 kHz
115
114
113
fS = 96 kHz
112
111
110
4.50
VCC = 5 V
VDD = 3.3 V
116
fS = 44.1 kHz
115
114
fS = 96 kHz
113
112
111
4.75
5.00
5.25
5.50
VCC – Supply Voltage – V
110
–50
–25
0
25
50
75
100
TA – Free-Air Temperature – °C
Figure 25
Figure 26
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
www.ti.com
21
PCM1730
SLES021 – NOVEMBER 2001
TYPICAL CHARACTERISTICS
–60-dB OUTPUT SPECTRUM
–60-dB OUTPUT SPECTRUM
0
0
VCC = 5 V
VDD = 3.3 V
fS = 44.1 kHz
TA = 25°C
BW = 20 kHz
–20
–40
–60
Amplitude – dB
Amplitude – dB
–40
–80
–100
–60
–80
–100
–120
–120
–140
–140
–160
0
5
VCC = 5 V
VDD = 3.3 V
fS = 44.1 kHz
TA = 25°C
BW = 100 kHz
–20
10
15
–160
20
0
20
f – Frequency – kHz
40
60
80
100
f – Frequency – kHz
Figure 27
Figure 28
TOTAL HARMONIC DISTORTION + NOISE
vs
INPUT LEVEL
THD+N – Total Harmonic Distortion + Noise – %
100
VCC = 5 V
VDD = 3.3 V
TA = 25°C
10
1
fS = 96 kHz
0.1
fS = 44.1 kHz
0.010
0.001
0.0001
–100
–80
–60
–40
–20
0
Input Level – dBFS
Figure 29
† All specifications at TA = 25°C, VDD = 3.3 V, VCC = 5 V, SCKI = 256 fS (fS = 44.1 kHz), and 24-bit input data (unless otherwise noted)
22
www.ti.com
MECHANICAL DATA
MSSO002D – JANUARY 1995 – REVISED SEPTEMBER 2000
MECHANICAL DATA
DB (R-PDSO-G**)
PLASTIC SMALL-OUTLINE
28 PINS SHOWN
0,38
0,22
0,65
28
0,15 M
15
0,15 NOM
8,20
7,40
5,60
5,00
Gage Plane
1
14
0,25
A
0°–ā8°
0,95
0,55
Seating Plane
2,00 MAX
0,10
0,05 MIN
PINS **
14
16
20
24
28
30
38
A MAX
6,50
6,50
7,50
8,50
10,50
10,50
12,90
A MIN
5,90
5,90
6,90
7,90
9,90
9,90
12,30
DIM
4040065 /D 09/00
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion not to exceed 0,15 mm.
Falls within JEDEC MO-150
www.ti.com
23
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, modifications,
enhancements, improvements, and other changes to its products and services at any time and to discontinue
any product or service without notice. Customers should obtain the latest relevant information before placing
orders and should verify that such information is current and complete. All products are sold subject to TI’s terms
and conditions of sale supplied at the time of order acknowledgment.
TI warrants performance of its hardware products to the specifications applicable at the time of sale in
accordance with TI’s standard warranty. Testing and other quality control techniques are used to the extent TI
deems necessary to support this warranty. Except where mandated by government requirements, testing of all
parameters of each product is not necessarily performed.
TI assumes no liability for applications assistance or customer product design. Customers are responsible for
their products and applications using TI components. To minimize the risks associated with customer products
and applications, customers should provide adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any TI patent right,
copyright, mask work right, or other TI intellectual property right relating to any combination, machine, or process
in which TI products or services are used. Information published by TI regarding third–party products or services
does not constitute a license from TI to use such products or services or a warranty or endorsement thereof.
Use of such information may require a license from a third party under the patents or other intellectual property
of the third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of information in TI data books or data sheets is permissible only if reproduction is without
alteration and is accompanied by all associated warranties, conditions, limitations, and notices. Reproduction
of this information with alteration is an unfair and deceptive business practice. TI is not responsible or liable for
such altered documentation.
Resale of TI products or services with statements different from or beyond the parameters stated by TI for that
product or service voids all express and any implied warranties for the associated TI product or service and
is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Mailing Address:
Texas Instruments
Post Office Box 655303
Dallas, Texas 75265
Copyright  2001, Texas Instruments Incorporated