PCM1770, PCM1771
SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
LOW-VOLTAGE AND LOW-POWER STEREO AUDIO DIGITAL-TO-ANALOG CONVERTER
WITH HEADPHONE AMPLIFIER
FEATURES
APPLICATIONS
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Multilevel DAC Including Headphone Amplifier
Analog Performance (VCC, VHP = 2.4 V):
– Dynamic Range: 98 dB Typ
– THD+N at 0 dB: 0.1% Typ
– THD+N at –20 dB: 0.04% Typ
– Output Power at RL = 16 Ω: 13 mW
(Stereo), 26 mW (Monaural)
1.6-V to 3.6-V Single Power Supply
Low Power Dissipation: 6.5 mW at VCC, VHP =
2.4 V
System Clock: 128 fS, 192 fS, 256 fS, 384 fS
Sampling Frequency: 5 kHz to 50 kHz
Software Control (PCM1770):
– 16-, 20-, 24-Bit Word Available
– Left-, Right-Justified, and I2S
– Slave/Master Selectable
– Digital Attenuation: 0 dB to –62 dB, 1
dB/Step
– 44.1-kHz Digital De-Emphasis
– Zero Cross Attenuation
– Digital Soft Mute
– Monaural Analog-In With Mixing
– Monaural Speaker Mode
Hardware Control (PCM1771):
– Left-Justified and I2S
– 44.1-kHz Digital De-Emphasis
– Monaural Analog-In With Mixing
Pop-Noise-Free Circuit
3.3-V Tolerant
Packages: TSSOP-16 and VQFN-20
Portable Audio Player
Cellular Phone
PDA
Other Applications Requiring Low-Voltage
Operation
DESCRIPTION
The PCM1770 and PCM1771 devices are CMOS,
monolithic, integrated circuits which include stereo
digital-to-analog converters, headphone circuitry, and
support circuitry in small TSSOP-16 and VQFN-20
packages.
The data converters use TI's enhanced multilevel ∆-Σ
architecture, which employs noise shaping and
multilevel amplitude quantization to achieve excellent
dynamic performance and improved tolerance to
clock jitter. The PCM1770 and PCM1771 devices
accept several industry standard audio data formats
with 16- to 24-bit data, left-justified, I2S, etc.,
providing easy interfacing to audio DSP and decoder
devices. Sampling rates up to 50 kHz are supported.
A full set of user-programmable functions is
accessible through a 3-wire serial control port, which
supports register write functions.
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.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2001–2007, Texas Instruments Incorporated
PCM1770, PCM1771
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted (1)
PCM1770
PCM1771
Supply voltage: VCC, VHP
–0.3 V to 4 V
Supply voltage differences: VCC, VHP
±0.1 V
Ground voltage differences
±0.1 V
Digital input voltage
–0.3 V to 4 V
Input current (any terminals except supplies)
±10 mA
Operating temperature
–40°C to 125°C
Storage temperature
–55°C to 150°C
Junction temperature
150°C
Lead temperature (soldering)
260°C, 5 s
Package temperature (IR reflow, peak)
(1)
260°C
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.
RECOMMENDED OPERATING CONDITIONS
over operating free-air temperature range
Supply voltage: VCC, VHP
MIN
NOM
MAX
1.6
2.4
3.6
V
0.64
19.2
MHz
5
50
kHz
Digital input logic family
Digital input clock frequency
CMOS
System clock
Sampling clock
Analog output load resistance
Ω
16
Analog input level (VHP = 2.4 V)
Operating free-air temperature, TA
2
UNIT
–25
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1.4
Vp-p
85
°C
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
ELECTRICAL CHARACTERISTICS
all specifications at TA = 25°C, VCC = VHP = 2.4 V, fS = 44.1 kHz, system clock = 256 fS and 24-bit data, RL = 16 Ω, unless
otherwise noted
PARAMETER
TEST CONDITIONS
PCM1770PW, PCM1771PW,
PCM1770RGA, PCM1771RGA
MIN
Resolution
TYP
UNIT
MAX
24
Bits
OPERATING FREQUENCY
Sampling frequency (fS)
5
System clock frequency
50
kHz
128f S, 192 fS, 256 fS, 384 fS
DIGITAL INPUT/OUTPUT (1) (2)
Logic family
VIH
CMOS compatible
0.7 VCC
Input logic level
VIL
IIH
Input logic current
IIL
VOH
Output logic level (3)
VOL
VDC
0.3 VCC
VIN = VCC
10
VIN = 0 V
–10
IOH = –2 mA
0.7 VCC
VDC
µA
µA
VDC
IOL = 2 mA
0.3 VCC
VDC
DYNAMIC PERFORMANCE (HEADPHONE OUTPUT)
THD+N
Full-scale output voltage
0 dB
Dynamic range
EIAJ, A-weighted
90
98
dB
Signal-to-noise ratio
EIAJ, A-weighted
90
98
dB
Total harmonic distortion + noise
0.55 VHP
0 dB (13 mW)
Vp-p
0.1%
–20 dB (0.1 mW)
0.04%
0.1%
Stereo
10
13
mWrms
Monaural
20
26
mWrms
Channel separation
64
72
dB
Load resistance
14
16
Ω
Output power
DC ACCURACY
Gain error
±2
±8
%FSR
Gain mismatch,
channel-to-channel
±2
±8
%FSR
±30
±75
mV
0.584 VHP
Vp-p
Bipolar zero error
VOUT = 0.5 VCC at BPZ
ANALOG LINE INPUT (MIXING CIRCUIT)
Analog input voltage range
Gain (analog input to headphone
output)
0.67
Analog input impedance
THD+N
10
Total harmonic distortion + noise AIN = 0.56 VHP (peak-to-peak)
kΩ
0.1%
DIGITAL FILTER PERFORMANCE
Pass band
0.454 fS
Stop band
0.546 fS
Pass-band ripple
±0.04
Stop-band attenuation
–50
dB
dB
Group
delay
20/fS
44.1-kHz de-emphasis error
±0.1
dB
ANALOG FILTER PERFORMANCE
(1)
(2)
(3)
Digital inputs and outputs are CMOS compatible.
All logic inputs are 3.3-V tolerant and not terminated internally.
LRCK and BCK terminals
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
ELECTRICAL CHARACTERISTICS (continued)
all specifications at TA = 25°C, VCC = VHP = 2.4 V, fS = 44.1 kHz, system clock = 256 fS and 24-bit data, RL = 16 Ω, unless
otherwise noted
PARAMETER
TEST CONDITIONS
PCM1770PW, PCM1771PW,
PCM1770RGA, PCM1771RGA
MIN
Frequency response
at 20 kHz
TYP
UNIT
MAX
±0.2
dB
POWER SUPPLY REQUIREMENTS
Voltage range, VCC, VHP
ICC
IHP
Supply current
1.6
2.4
3.6
BPZ input
1.5
2.5
BPZ input
1.2
2.5
5
15
µA
BPZ input
6.5
12
mW
Power down (4)
12
36
µW
85
°C
Power down (4)
ICC + IHP
Power dissipation
VDC
mA
TEMPERATURE RANGE
Operation temperature
θJA
(4)
4
Thermal resistance
–25
PCM1770PW, -71PW: 16-terminal TSSOP
150
PCM1770RGA, -71RGA: 20-terminal VQFN
130
All input signals are held static.
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
PIN ASSIGNMENTS
PCM1770
PW PACKAGE
(TOP VIEW)
LRCK
DATA
BCK
PD
AGND
HGND
VCOM
HOUTR
PCM1771
PW PACKAGE
(TOP VIEW)
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
SCKI
MS
MC
MD
VCC
VHP
AIN
HOUTL
LRCK
DATA
BCK
PD
AGND
HGND
VCOM
HOUTR
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
SCKI
FMT
AMIX
DEMP
VCC
VHP
AIN
HOUTL
P0001-02
PCM1770
RGA PACKAGE
(TOP VIEW)
2
14
3
13
4
12
5
7
8
11
9 10
VCOM
HOUTR
NC
HOUTL
6
MS
MC
MD
VCC
VHP
DATA
BCK
PD
AGND
HGND
1
20 19 18 17 16
15
2
14
AMIX
3
13
DEMP
4
12
VCC
11
9 10
VHP
5
6
7
8
NC − No internal connection
FMT
AIN
20 19 18 17 16
15
VCOM
HOUT R
NC
HOUTL
1
AIN
DATA
BCK
PD
AGND
HGND
LRCK
NC
NC
NC
SCKI
LRCK
NC
NC
NC
SCKI
PCM1771
RGA PACKAGE
(TOP VIEW)
P0002-02
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
TERMINAL FUNCTIONS
PCM1770PW
TERMINAL
NAME
6
NO.
I/O
DESCRIPTION
AGND
5
–
Analog ground. This is a return for VCC.
AIN
10
I
Monaural analog signal mixer input. The signal can be mixed with the outputs of the L- and R-channel DACs.
BCK
3
I/O
DATA
2
I
Serial audio data input
HGND
6
–
Analog ground. This is a return for VHP.
HOUTL
9
O
L-channel analog signal output of the headphone amplifiers
HOUTR
8
O
R-channel analog signal output of the headphone amplifiers
LRCK
1
I/O
Left and right clock. Determines which channel is being input on the audio data input, DATA. The frequency of
LRCK must be the same as the audio sampling rate. In the slave interface mode, this clock is input from an
external device. In the master interface mode, the PCM1770 device generates the LRCK output to an external
device.
MC
14
I
Mode control port serial bit clock input. Clocks the individual bits of the control data input, MD.
MD
13
I
Mode control port serial data input. Controls the operation mode on the PCM1770 device.
MS
15
I
Mode control port select. The control port is active when this terminal is low.
PD
4
I
Reset input. When low, the PCM1770 device is powered down, and all mode control registers are reset to
default settings.
SCKI
16
I
System clock input
VCC
12
–
Power supply for all analog circuits except the headphone amplifier.
VCOM
7
–
Decoupling capacitor connection. An external 10-µF capacitor connected from this terminal to analog ground is
required for noise filtering. Voltage level of this terminal is 0.5 VHP nominal.
VHP
11
–
Analog power supply for the headphone amplifier circuits. The voltage level must be the same as VCC.
Serial bit clock. Clocks the individual bits of the audio data input, DATA. In the slave interface mode, this clock
is input from an external device. In the master interface mode, the PCM1770 device generates the BCK output
to an external device.
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TERMINAL FUNCTIONS (CONTINUED)
PCM1770RGA
TERMINAL
NAME
NO.
I/O
DESCRIPTION
AGND
4
–
Analog ground. This is a return for VCC.
AIN
10
I
Monaural analog signal mixer input. The signal can be mixed with the outputs of the L- and R-channel DACs.
BCK
2
I/O
DATA
1
I
Serial audio data input
HGND
5
–
Analog ground. This is a return for VHP.
HOUTL
9
O
L-channel analog signal output of the headphone amplifiers
HOUTR
7
O
R-channel analog signal output of the headphone amplifiers
LRCK
20
I/O
Left and right clock. Determines which channel is being input on the audio data input, DATA. The frequency of
LRCK must be the same as the audio sampling rate. In the slave interface mode, this clock is input from an
external device. In the master interface mode, the PCM1770 device generates the LRCK output to an external
device.
MC
14
I
Mode control port serial bit clock input. Clocks the individual bits of the control data input, MD.
MD
13
I
Mode control port serial data input. Controls the operation mode on the PCM1770 device.
MS
15
I
Mode control port select. The control port is active when this terminal is low.
NC
8, 17,
18, 19
–
No connect
PD
3
I
Reset input. When low, the PCM1770 device is powered down, and all mode control registers are reset to
default settings.
SCKI
16
I
System clock input
VCC
12
–
Power supply for all analog circuits except the headphone amplifier.
VCOM
6
–
Decoupling capacitor connection. An external 10-µF capacitor connected from this terminal to analog ground is
required for noise filtering. Voltage level of this terminal is 0.5 VHP nominal.
VHP
11
–
Analog power supply for the headphone amplifier circuits. The voltage level must be the same as VCC.
Serial bit clock. Clocks the individual bits of the audio data input, DATA. In the slave interface mode, this clock
is input from an external device. In the master interface mode, the PCM1770 device generates the BCK output
to an external device.
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
TERMINAL FUNCTIONS (CONTINUED)
PCM1771PW
TERMINAL
NAME
NO.
I/O
DESCRIPTION
AGND
5
–
Analog ground. This is a return for VCC.
AIN
10
–
Monaural analog signal mixer input. The signal can be mixed with the outputs of the L- and R-channel DACs.
AMIX
14
I
Analog mixing control
BCK
3
I
Serial bit clock. Clocks the individual bits of the audio data input, DATA.
DATA
2
I
Serial audio data input
DEMP
13
I
De-emphasis control
FMT
15
I
Data format select
HGND
6
–
Analog ground. This is a return for VHP.
HOUTL
9
O
L-channel analog signal output of the headphone amplifiers
HOUTR
8
O
R-channel analog signal output of the headphone amplifiers
LRCK
1
I
Left and right clock. Determines which channel is being input on the audio data input, DATA. The frequency of
LRCK must be the same as the audio sampling rate.
PD
4
I
Reset input. When low, the PCM1771 device is powered down, and all mode control registers are reset to
default settings.
SCKI
16
I
System clock input
VCC
12
–
Power supply for all analog circuits except the headphone amplifier.
VCOM
7
–
Decoupling capacitor connection. An external 10-µF capacitor connected from this terminal to analog ground is
required for noise filtering. Voltage level of this terminal is 0.5 VHP nominal.
VHP
11
–
Analog power supply for the headphone amplifier circuits. The voltage level must be the same as VCC.
PCM1771RGA
TERMINAL
NAME
8
NO.
I/O
DESCRIPTION
AGND
4
–
Analog ground. This is a return for VCC.
AIN
10
–
Monaural analog signal mixer input. The signal can be mixed with the outputs of the L- and R-channel DACs.
AMIX
14
I
Analog mixing control
BCK
2
I
Serial bit clock. Clocks the individual bits of the audio data input, DATA.
DATA
1
I
Serial audio data input
DEMP
13
I
De-emphasis control
FMT
15
I
Data format select
HGND
5
–
Analog ground. This is a return for VHP.
HOUTL
9
O
L-channel analog signal output of the headphone amplifiers
HOUTR
7
O
R-channel analog signal output of the headphone amplifiers
LRCK
20
I
Left and right clock. Determines which channel is being input on the audio data input, DATA. The frequency of
LRCK must be the same as the audio sampling rate.
NC
8, 17,
18, 19
–
No connect
PD
3
I
Reset input. When low, the PCM1771 device is powered down, and all mode control registers are reset to
default settings.
SCKI
16
I
System clock input
VCC
12
–
Power supply for all analog circuits except the headphone amplifier
VCOM
6
–
Decoupling capacitor connection. An external 10-µF capacitor connected from this terminal to analog ground is
required for noise filtering. Voltage level of this terminal is 0.5 VHP nominal.
VHP
11
–
Analog power supply for the headphone amplifier circuits. The voltage level must be the same as VCC.
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FUNCTIONAL BLOCK DIAGRAM
AIN
Digital
Attenuator
LRCK
×8
Digital
Filter
Audio
Interface
DATA
Headphone
Amplifier
∆Σ
DAC
+
HOUTR
BCK
VCOM
(FMT) MS
×8
Digital
Filter
SPI
Port
(AMIX) MC
∆Σ
DAC
+
VCOM
HOUTL
(DEMP) MD
Clock Manager
Power Supply
SCKI
PD
( ) : PCM1771
AGND
HGND
VCC
VHP
B0001-02
TYPICAL PERFORMANCE CURVES
All specifications at TA = 25°C, VCC = VHP 2.4 V, fS = 44.1 kHz, system clock = 256 fS, 24-bit data, and RL = 16 Ω, unless
otherwise noted.
Digital Filter
Digital Filter (De-Emphasis Off)
AMPLITUDE
vs
FREQUENCY
AMPLITUDE
vs
FREQUENCY
0
0.05
0.04
−20
0.03
0.02
Amplitude – dB
Amplitude – dB
−40
−60
−80
0.01
0.00
−0.01
−0.02
−100
−0.03
−120
−0.04
−140
0
1
2
f – Frequency [ fS]
3
−0.05
0.0
4
G001
Figure 1.
0.1
0.2
0.3
f – Frequency [ fS]
0.4
0.5
G002
Figure 2.
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SLES011E – SEPTEMBER 2001 – REVISED MARCH 2007
TYPICAL PERFORMANCE CURVES (continued)
All specifications at TA = 25°C, VCC = VHP 2.4 V, fS = 44.1 kHz, system clock = 256 fS, 24-bit data, and RL = 16 Ω, unless
otherwise noted.
De-Emphasis Curves
DE-EMPHASIS ERROR
vs
FREQUENCY
0
0.5
−1
0.4
−2
0.3
De-Emphasis Error – dB
De-Emphasis Level – dB
DE-EMPHASIS LEVEL
vs
FREQUENCY
−3
−4
−5
−6
−7
0.1
0.0
−0.1
−0.2
−8
−0.3
−9
−0.4
−10
0.0
−0.5
0.1
0.2
0.3
0.4
0.5
f – Frequency [ fS]
0.6
0
4
6
8
10
12
14
16
18
20
G003
G004
Figure 3.
Figure 4.
TOTAL HARMONIC DISTORTION + NOISE
vs
SUPPLY VOLTAGE
DYNAMIC RANGE
vs
SUPPLY VOLTAGE
104
Dynamic Range – dB
102
0 dB
0.10
0.1
–20 dB
100
98
96
94
0.01
1.2
1.6
2.0
2.4
2.8
3.2
VCC – Supply Voltage – V
3.6
4.0
92
1.2
G005
Figure 5.
10
2
f – Frequency – kHz
1.00
1
THD+N – Total Harmonic Distortion + Noise – %
0.2
1.6
2.0
2.4
2.8
Figure 6.
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3.2
VCC – Supply Voltage – V
3.6
4.0
G006
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TYPICAL PERFORMANCE CURVES (continued)
All specifications at TA = 25°C, VCC = VHP 2.4 V, fS = 44.1 kHz, system clock = 256 fS, 24-bit data, and RL = 16 Ω, unless
otherwise noted.
CHANNEL SEPARATION
vs
SUPPLY VOLTAGE
104
78
102
76
Channel Separation – dB
SNR – Signal-to-Noise Ratio − dB
SIGNAL-TO-NOISE RATIO
vs
SUPPLY VOLTAGE
100
98
96
1.6
2.0
2.4
2.8
3.2
3.6
VCC – Supply Voltage – V
70
66
1.2
4.0
1.6
2.0
2.4
2.8
3.2
3.6
VCC – Supply Voltage – V
G007
Figure 7.
Figure 8.
TOTAL HARMONIC DISTORTION + NOISE
vs
FREE-AIR TEMPERATURE
DYNAMIC RANGE
vs
FREE-AIR TEMPERATURE
1.00
1
4.0
G008
102
101
100
Dynamic Range – dB
THD+N – Total Harmonic Distortion + Noise – %
72
68
94
92
1.2
74
0 dB
0.10
0.1
–20 dB
99
98
97
96
95
0.01
−40
−20
0
20
40
60
80
TA – Free-Air Temperature – °C
100
94
−40
G009
Figure 9.
−20
0
20
40
60
TA – Free-Air Temperature – °C
80
100
G010
Figure 10.
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TYPICAL PERFORMANCE CURVES (continued)
All specifications at TA = 25°C, VCC = VHP 2.4 V, fS = 44.1 kHz, system clock = 256 fS, 24-bit data, and RL = 16 Ω, unless
otherwise noted.
CHANNEL SEPARATION
vs
FREE-AIR TEMPERATURE
102
76
101
75
100
74
Channel Separation – dB
99
98
97
96
95
94
−40
72
71
70
69
−20
0
20
40
60
80
68
−40
100
TA – Free-Air Temperature – °C
0
20
40
60
80
100
TA – Free-Air Temperature – °C
G011
Figure 12.
SUPPLY CURRENT
vs
SUPPLY VOLTAGE
SUPPLY CURRENT
vs
SAMPLING FREQUENCY
G012
20
5.0
20
4.5
18
4.5
18
4.0
16
4.0
16
3.5
14
3.5
14
Operational
3.0
12
2.5
10
2.0
8
1.5
6
Power Down
1.0
4
0.5
2
2.0
2.4
2.8
3.2
VCC – Supply Current – V
3.6
3.0
12
Operational
2.5
10
2.0
8
Power Down
1.5
6
1.0
4
0.5
2
0.0
0
1.6
ICC – Supply Current, Operational – mA
5.0
0.0
1.2
0
0
4.0
G013
Figure 13.
12
−20
Figure 11.
ICC – Supply Current, Power Down – µA
ICC – Supply Current, Operational – mA
73
ICC – Supply Current, Power Down – µA
SNR – Signal-to-Noise Ratio − dB
SIGNAL-TO-NOISE RATIO
vs
FREE-AIR TEMPERATURE
10
20
30
fS – Sampling Frequency – kHz
Figure 14.
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40
50
G014
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TYPICAL PERFORMANCE CURVES (continued)
All specifications at TA = 25°C, VCC = VHP 2.4 V, fS = 44.1 kHz, system clock = 256 fS, 24-bit data, and RL = 16 Ω, unless
otherwise noted.
DYNAMIC RANGE
vs
JITTER
100
Dynamic Range – dB
99
98
97
96
95
94
0
100
200
300
400
500
600
700
Jitter – ps
G015
Figure 15.
OUTPUT SPECTRUM (-60 dB, N = 8192)
0
0
−20
−20
−40
−40
Amplitude – dB
Amplitude – dB
OUTPUT SPECTRUM (-60 dB, N = 8192)
−60
−80
−60
−80
−100
−100
−120
−120
−140
−140
0
5
10
15
20
0
f – Frequency – kHz
20
40
60
80
100
120
f – Frequency – kHz
G016
Figure 16.
G017
Figure 17.
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DETAILED DESCRIPTION
System Clock, Reset, and Functions
System Clock Input
The PCM1770 and PCM1771 devices require a system clock for operating the digital interpolation filters and
multilevel ∆-Σ modulators. The system clock is applied at terminal 16 (SCKI). Table 1 shows examples of system
clock frequencies for common audio sampling rates.
Figure 18 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.
Table 1. System Clock Frequency for Common Audio Sampling Frequencies
SYSTEM CLOCK FREQUENCY, SCKI (MHz)
SAMPLING FREQUENCY, LRCK
128 fS
192 fS
256 fS
384 fS
48 kHz
6.144
9.216
12.288
18.432
44.1 kHz
5.6448
8.4672
11.2896
16.9344
32 kHz
4.096
6.144
8.192
12.288
24 kHz
3.072
4.608
6.144
9.216
22.05 kHz
2.8224
4.2336
5.6448
8.4672
16 kHz
2.048
3.072
4.096
6.144
12 kHz
1.536
2.304
3.072
4.608
11.025 kHz
1.4112
2.1168
2.8224
4.2336
8 kHz
1.024
1.536
2.048
3.072
t(SCKH)
0.7 VCC
SCKI
0.3 VCC
t(SCKL)
t(SCKY)
T0005-02
MIN
UNIT
t(SCKH)
System clock pulse duration, HIGH
PARAMETER
7
ns
t(SCKL)
System clock pulse duration, LOW
7
ns
t(SCKY)
System clock pulse cycle time(1)
52
ns
(1)
1/(128 fS), 1/(192 fS), 1/(256 fS) or 1/(384 fS)
Figure 18. System Clock Timing
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Power On/Off Reset
The PCM1770/71 always must have the PD pin set from LOW to HIGH once after power-supply voltages VCC
and VHP have reached the specified voltage range and stable clocks SCKI, BCK, and LRCK are being supplied
for the power-on sequence. A minimum time of 1 ms after both the clock and power-supply requirements are
met is required before the PD pin changes from LOW to HIGH, as shown in Figure 19. Subsequent to the PD
LOW-to-HIGH transition, the internal logic state is held in reset for 1024 system clock cycles prior to the start of
the power-on sequence. During the power-on sequence, HOUTL and HOUTR increase gradually from ground
leved, reaching an output level that corresponds to the input data after a period of 9334/fS. When powering off,
the PD pin is set from HIGH to LOW first. Then HOUTL and HOUTR decrease gradually to ground level over a
period of 9334/fS, as shown in Figure 20, after which power can be removed without creating pop noise. When
powering on or off, adhering to the timing requirements of Figure 19 and Figure 20 ensures that pop noise does
not occur. If the timing requirements are not met, pop noise might occur.
VCC, VHP
0V
1 ms (Min)
1024 Internal System Clocks
LRCK, BCK, SCKI
1 ms (Min)
PD
Internal Reset
9334/fS
HOUTL, HOUTR
0V
T0006-02
Figure 19. Power-On Sequence
VCC, VHP
0V
LRCK, BCK, SCKI
9334/fS
PD
HOUTL, HOUTR
0V
T0007-02
Figure 20. Power-Off Sequence
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Power-Up/-Down Sequence and Reset
The PCM1770 device has two kinds of power-up/-down methods: the PD terminal through hardware control and
PWRD (register 4, B0) through software control. The PCM1771 device has only the PD terminal through
hardware control for the power-up/-down sequence. The power-up or power-down sequence operates the same
as the power-on or power-off sequence. When powering up or down using the PD terminal, all digital circuits are
reset. When powering up or down using PWRD, all digital circuits are reset except for maintaining the logic
states of the registers. Figure 21 shows the power-up/power-down sequence.
2.4 V
VCC, VHP
9334/fS
9334/fS
LRCK, BCK, SCKI
PD
HOUTL, HOUTR
0V
T0008-02
Figure 21. Power-Down and Power-Up Sequences
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Audio Serial Interface
The audio serial interface for the PCM1770 and PCM1771 devices consists of a 3-wire synchronous serial port.
It includes terminals 1 (LRCK), 2 (DATA), and 3 (BCK). BCK is the serial audio bit clock, and it clocks the serial
data present on DATA into the audio interface serial shift register. Serial data is clocked into the PCM1770 and
PCM1771 devices on the rising edge of BCK. LRCK is the serial audio left/right word clock. It latches serial data
into the serial audio interface internal registers.
Both LRCK and BCK of the PCM1770 device support the slave and master modes, which are set by FMT
(register 3). LRCK and BCK are outputs during the master mode and inputs during the slave mode.
In slave mode, BCK and LRCK are synchronous to the audio system clock, SCKI. Ideally, it is recommended
that LRCK and BCK be derived from SCKI. LRCK is operated at the sampling frequency, fS. BCK can be
operated at 32, 48, or 64 times the sampling frequency.
In master mode, BCK and LRCK are derived from the system clock and these terminals are outputs. BCK and
LRCK are synchronous to SCKI. LRCK is operated at the sampling frequency, fS. BCK can be operated at 64
times the sampling frequency.
The PCM1770 and PCM1771 devices operate under LRCK synchronized with the system clock. The PCM1770
and PCM1771 devices do not need a specific phase relationship between LRCK and the system clock, but do
require the synchronization of LRCK and the system clock. If the relationship between the system clock and
LRCK changes more than ±3 BCK during one sample period, internal operation of the PCM1770 and PCM1771
devices halts within 1/fS, and the analog output is kept in last data until resynchronization between system clock
and LRCK is completed.
Audio Data Formats and Timing
The PCM1770 device supports industry-standard audio data formats, including standard, I2S, and left-justified.
The PCM1771 device supports the I2S and left-justified data formats. Table 2 lists the main features of the audio
data interface. Figure 22 shows the data formats. Data formats are selected using the format bits, FMT[2:0] of
control register 3 in the case of the PCM1770 device, and are selected using the FMT terminal in the case of the
PCM1771 device. The default data format is 24-bit, left-justified, slave mode. All formats require binary 2s
complement, MSB-first audio data. Figure 23 shows a detailed timing diagram for the serial audio interface in
slave mode. Figure 24 shows a detailed timing diagram for the serial audio interface in master mode.
Table 2. Audio Data Interface
AUDIO-DATA INTERFACE FEATURE
Audio data interface format
CHARACTERISTIC
(PCM1770)
Standard, I2S, left-justified
(PCM1771)
I2S, left-justified
Audio data bit length
16-, 20-, 24-bit selectable
Audio data format
MSB-first, 2s-complement
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(1) Standard Data Format; L-Channel = HIGH, R-Channel = LOW (Slave Mode)
1/fS
LRCK
R-Channel
L-Channel
BCK
(= 32 fS, 48 fS or 64 fS)
16-Bit Right-Justified, BCK = 32 fS
DATA 14 15 16
1
2
3
14 15 16
1
LSB
MSB
2
3
14 15 16
LSB
MSB
16-Bit Right-Justified, BCK = 48 fS or 64 fS
DATA 14 15 16
1
2
3
14 15 16
MSB
1
LSB
2
3
14 15 16
MSB
LSB
20-Bit Right-Justified
DATA 18 19 20
1
2
3
18 19 20
MSB
1
LSB
2
3
18 19 20
MSB
LSB
24-Bit Right-Justified
DATA 22 23 24
1
2
3
22 23 24
MSB
1
LSB
2
3
22 23 24
MSB
LSB
(2) I2S Data Format; L-Channel = LOW, R-Channel = HIGH (Slave Mode)
1/fS
LRCK
R-Channel
L-Channel
BCK
(= 32 fS, 48 fS or 64 fS)
DATA
1
2
3
N−2 N−1
MSB
N
1
LSB
2
3
N−2 N−1
MSB
N
1
2
LSB
(3) Left-Justified Data Format; L-Channel = HIGH, R-Channel = LOW (Slave Mode)
1/fS
LRCK
L-Channel
R-Channel
BCK
(= 32 fS, 48 fS or 64 fS)
DATA
1
2
3
MSB
N−2
N−1
N
1
LSB
2
3
N−2 N−1
MSB
N
1
2
N
1
2
LSB
(4) Left-Justified Data Format; L-Channel = HIGH, R-Channel = LOW (Master Mode)
(The frequency of BCK is 64 fS and SCKI is 256 fS only)
1/fS
LRCK
L-Channel
R-Channel
BCK
(= 64 fS)
DATA
1
2
3
MSB
N−2
N−1
LSB
N
1
2
3
MSB
N−2 N−1
LSB
T0009-01
Figure 22. Audio Data Input Formats
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50% of VCC
LRCK (Input)
t(BCL)
t(BCH)
t(LB)
50% of VCC
BCK (Input)
t(BCY)
t(BL)
50% of VCC
DATA
t(DS)
t(DH)
PARAMETER
T0010-02
MIN
MAX
UNIT
)(1)
t(BCY)
BCK pulse cycle time
1/(64 fS
t(BCH)
BCK high-level time
35
ns
t(BCL)
BCK low-level time
35
ns
t(BL)
BCK rising edge to LRCK edge
10
ns
t(LB)
LRCK edge to BCK rising edge
10
ns
t(DS)
DATA set-up time
10
ns
t(DH)
DATA hold time
10
ns
(1)
fS is the sampling frequency.
Figure 23. Audio Interface Timing (Slave Mode)
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t(SCY)
50% of VCC
SCKI
t(DL)
50% of VCC
LRCK (Output)
t(BCL)
t(BCH)
t(DB)
t(DB)
50% of VCC
BCK (Output)
t(BCY)
50% of VCC
DATA
t(DS)
t(DH)
T0011-02
PARAMETER
MIN
MAX
UNIT
0
40
ns
0
40
ns
1/(256 fS)(1)
t(SCY)
SCKI pulse cycle time
t(DL)
LRCK edge from SCKI rising edge
t(DB)
BCK edge from SCKI rising edge
t(BCY)
BCK pulse cycle time
t(BCH)
BCK high-level time
146
ns
t(BCL)
BCK low-level time
146
ns
t(DS)
DATA setup time
10
ns
t(DH)
DATA hold time
10
ns
(1)
1/(64 fS)(1)
fS is up to 48 kHz. fS is the sampling frequency.
Figure 24. Audio Interface Timing (Master Mode)
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Hardware Control (PCM1771)
The digital functions of the PCM1771 device are capable of hardware control. Table 3 shows selectable formats,
Table 4 shows de-emphasis control, and Table 5 shows analog mixing control.
Table 3. Data Format Select
FMT
DATA FORMAT
Low
16- to 24-bit, left-justified format
High
16- to 24-bit, I2S format
Table 4. De-Emphasis Control
DEMP
DE-EMPHASIS FUNCTION
Low
44.1-kHz de-emphasis OFF
High
44.1-kHz de-emphasis ON
Table 5. Analog Mixing Control
AMIX
ANALOG MIXING
Low
Analog mixing OFF
High
Analog mixing ON
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Software Control (PCM1770)
The PCM1770 device has many programmable functions that can be controlled in the software-control mode.
The functions are controlled by programming the internal registers using MS, MC, and MD.
The software-control interface is a 3-wire serial port that operates asynchronously to the serial audio interface.
The serial control interface is used to program the on-chip mode registers. MD is the serial data input, used to
program the mode registers. MC is the serial bit clock, used to shift data into the control port. MS is the mode
control port select signal.
Register Write Operation (PCM1770)
All write operations for the serial control port use 16-bit data words. Figure 25 shows the control data word
format. The most significant bit must be 0. There are seven bits, labeled IDX[6:0], that set the register index (or
address) for the write operation. The eight least significant bits, D[7:0], contain the data to be written to the
register specified by IDX[6:0].
Figure 26 shows the functional timing diagram for writing to the serial control port. To write data into the mode
register, the data is clocked into an internal shift register on the rising edge of the MC clock. Serial data can
change on the falling edge of the MC clock and must be stable on the rising edge of the MC clock. The MS
signal must be low during the write mode and the rising edge of the MS signal must be aligned with the falling
edge of the last MC clock pulse in the 16-bit frame. The MC clock can run continuously between transactions
while the MS signal is low.
LSB
MSB
0
IDX6
IDX5
IDX4
IDX3
IDX2
IDX1
IDX0
D7
D6
D5
Register Index (or Address)
D4
D3
D2
D1
D0
Register Data
R0001-01
Figure 25. Control Data Word Format for MD
(1) Single Write Operation
16 Bits
MS
MC
MD
MSB
LSB
MSB
(2) Continuous Write Operation
16 Bits x N Frames
MS
MC
MD
MSB
LSB
MSB
LSB
MSB
LSB
N Frames
T0012-01
Figure 26. Register Write Operation
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Control Interface Timing Requirements (PCM1770)
Figure 27 shows a detailed timing diagram for the serial control interface. These timing parameters are critical
for proper control port operation.
t(MHH)
MS
50% of VCC
t(MLS)
t(MCL)
t(MCH)
t(MLH)
MC
50% of VCC
t(MCY)
LSB
MD
50% of VCC
t(MDS)
t(MDH)
T0013-02
PARAMETER
SYMBOL
MIN
MC pulse cycle time
t(MCY)
100(1)
TYP
MAX
ns
MC low-level time
t(MCL)
50
ns
MC high-level time
t(MCH)
50
ns
MS high-level time
t(MHH)
(2)
ns
MS falling edge to MC rising edge
t(MLS)
20
ns
MS hold time
t(MLH)
20
ns
MD hold time
t(MDH)
15
ns
MD setup time
t(MDS)
20
ns
(1)
When MC runs continuously between transactions, MC pulse cycle time is specified as 3/(128 fS), where fS is
sampling rate.
(2)
3/(128 fS) s (min), where fS is sampling rate.
UNIT
Figure 27. Control Interface Timing
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Mode Control Registers (PCM1770)
User-Programmable Mode Controls
The PCM1770 device has a number of user-programmable functions that can be accessed via mode control
registers. The registers are programmed using the serial control interface, as discussed in the Software Control
(PCM1770) section. Table 6 lists the available mode control functions, along with their reset default conditions
and associated register index.
Register Map
Table 7 shows the mode control register map. Each register includes an index (or address) indicated by the
IDX[6:0] bits.
Table 6. User-Programmable Mode Controls
FUNCTION
RESET DEFAULT
Soft mute control, L/R independently
BIT(S)
Disabled
01
MUTL, MUTR
0 dB
01, 02
ATL[5:0], ATR[5:0]
OVER
Digital attenuation level setting, 0 dB to –63 dB in 1-dB steps, L/R
independently
Oversampling rate control (128 fS, 192 fS, 256 fS, 384 fS)
REGISTER NO.
128 fS oversampling
03
Polarity control for analog output for R-channel DAC
Not inverted
03
RINV
Analog mixing control for analog in, AIN (terminal 14)
Disabled
03
AMIX
44.1-kHz de-emphasis control
Disabled
03
DEM
24-bit, left-justified format
03
FMT[2:0]
Zero cross attenuation
Disabled
04
ZCAT
Power-down control
Disabled
04
PWRD
Audio data format select
Table 7. Mode Control Register Map
REGIS IDX [6:0] B15
TER
(B14-B8)
B14
B13
B12
B11
B10
B9
B8
B7
B6
B5
B4
B3
B2
B1
B0
01
01h
0
IDX6 IDX5 IDX4 IDX3 IDX2 IDX1 IDX0 MUTR MUTL
ATL5
ATL4
ATL3
ATL2
ATL1
ATL0
02
02h
0
IDX6 IDX5 IDX4 IDX3 IDX2 IDX1 IDX0
ATR5
ATR4
ATR3
ATR2
ATR1
ATR0
RINV
AMIX
DEM
FMT2
FMT1
FMT0
ZCAT
RSV
RSV
RSV
PWR
(1)
(1)
(1)
03
03h
0
RSV
RSV
(1)
(1)
IDX6 IDX5 IDX4 IDX3 IDX2 IDX1 IDX0 OVER
RSV
(1)
04
(1)
24
04h
0
IDX6 IDX5 IDX4 IDX3 IDX2 IDX1 IDX0
RSV
RSV
RSV
(1)
(1)
(1)
RSV is reserved for test operation. It must be set to 0 during regular operation.
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Register Definitions
Register 01
B15
0
B14
IDX6
B13
IDX5
B12
IDX4
B11
IDX3
B10
IDX2
B9
IDX1
B8
IDX0
B7
MUTR
B6
MUTL
B5
ATL5
B4
ATL4
B3
ATL3
B2
ATL2
B1
ATL1
B0
ATL0
IDX[6:0]: 000 0001b
MUTx: Soft Mute Control
Where, x = L or R, corresponding to the headphone output HOUTL or HOUTR.
Default value: 0
MUTL, MUTR = 0 Mute disabled (default)
MUTL, MUTR = 1 Mute enabled
The mute bits, MUTL and MUTR, enable or disable the soft mute function for the corresponding headphone
outputs, HOUTL and HOUTR. The soft mute function is incorporated into the digital attenuators. When mute is
disabled (MUTx = 0), the attenuator and DAC operate normally. When mute is enabled by setting MUTx = 1, the
digital attenuator for the corresponding output is decreased from the current setting to the infinite attenuation,
one attenuator step (1 dB) at a time. This provides pop-free muting of the headphone output.
By setting MUTx = 0, the attenuator is increased one step at a time to the previously programmed attenuation
level.
ATL[5:0]: Digital Attenuation Level Setting for Headphone Output, HOUTL
Default value: 11 1111b
Headphone output HOUTL includes a digital attenuation function. The attenuation level can be set from 0 dB to
–62 dB, in 1-dB steps. Changes in attenuator levels are made by incrementing or decrementing by one step (1
dB) for every 8/fS time internal until the programmed attenuator setting is reached. Alternatively, the attenuation
level may be set to infinite attenuation (or mute).
The following table shows the attenuation levels for various settings:
ATL[5:0]
ATTENUATION LEVEL SETTING
11 1111b
0 dB, no attenuation (default)
11 1110b
–1 dB
11 1101b
–2 dB
:
:
00 0010b
–61 dB
00 0001b
–62 dB
00 0000b
Mute
Register 02
B15
0
B14
IDX6
B13
IDX5
B12
IDX4
B11
IDX3
B10
IDX2
B9
IDX1
B8
IDX0
B7
RSV
B6
RSV
B5
ATR5
B4
ATR4
B3
ATR3
B2
ATR2
B1
ATR1
B0
ATR0
IDX[6:0]: 000 0010b
ATR[5:0]: Digital Attenuation Level Setting for Headphone Output, HOUTR
Default value: 11 1111b
Headphone output HOUTR includes a digital attenuation function. The attenuation level can be set from 0 dB to
–62 dB, in 1-dB steps. Changes in attenuator levels are made by incrementing or decrementing by one step (1
dB) for every 8/fS time internal until the programmed attenuator setting in reached. Alternatively, the attenuation
level can be set to infinite attenuation (or mute).
To set the attenuation levels for ATR[5:0], see the table for ATL[5:0], register 01.
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Register 03
B15
0
B14
IDX6
B13
IDX5
B12
IDX4
B11
IDX3
B10
IDX2
B9
IDX1
B8
IDX0
B7
OVER
B6
RSV
B5
RINV
B4
AMIX
B3
DEM
B2
FMT2
B1
FMT1
B0
FMT0
IDX[6:0]: 000 0011b
OVER: Oversampling Control
Default value: 0
OVER = 0
128fS oversampling
OVER = 1
192fS, 256fS, 384fS oversampling
The OVER bit controls the oversampling rate of the ∆-Σ D/A converters. When it operates at a low sampling
rate, less than 24 kHz, this function is recommended.
RINV: Polarity Control for Headphone Output, HOUTR
Default value: 0
RINV = 0
Not inverted
RINV = 1
Inverted output
The RINV bits allow the user to control the polarity of the headphone output, HOUTR. This function can be used
to connect the monaural speaker using the BTL connection method. This bit is recommended to be 0 during the
power-up/-down sequence for minimizing audible pop noise.
AMIX: Analog Mixing Control for External Analog Signal, AIN
Default value: 0
AMIX = 0
Disabled (not mixed)
AMIX = 1
Enabled (mixing to the DAC output)
The AMIX bit allows the user to mix analog input (AIN) with headphone outputs (HOUTL/HOUTR) internally.
DEM: 44.1-kHz De-Emphasis Control
Default value: 0
DEM = 0
Disabled
DEM = 1
Enabled
The DEM bit enables or disables the digital de-emphasis filter for the 44.1-kHz sampling rate.
FMT[2:0]: Audio Interface Data Format
Default value: 000
The FMT[2:0] bits select the data format for the serial audio interface. The following table shows the available
format options.
FMT[2:0]
Audio Data Format Selection
000
16- to 24-bit, left-justified format (default)
001
16- to 24-bit, I2S format
010
24-bit right-justified data
011
20-bit right-justified data
100
16-bit right-justified data
101
16- to 24-bit, left-justified format, master mode
110
Reserved
111
Reserved
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Register 04
B15
0
B14
IDX6
B13
IDX5
B12
IDX4
B11
IDX3
B10
IDX2
B9
IDX1
B8
IDX0
B7
RSV
B6
RSV
B5
RSV
B4
ZCAT
B3
RSV
B2
RSV
B1
RSV
B0
PWRD
IDX[6:0]: 0000 0100b
ZCAT: Zero Cross Attenuation
Default value: 0
ZCAT = 0
Normal attenuation (default)
ZCAT = 1
Zero cross attenuation
This bit enables changing the signal level on zero crossing during attenuation control or muting. If the signal
does not cross BPZ beyond 512/fS (11.6 ms at 44.1-kHz sampling rate), the signal level is changed similarly to
normal attenuation control. This function is independently monitored for each channel; moreover, change of
signal level is alternated between both channels. Figure 28 shows an example of zero cross attenuation.
ATT CTRL START
L-Channel
(1.5 kHz)
R-Channel
(1 kHz)
Level Change Point
W0001-01
Figure 28. Example of Zero Cross Attenuation
PWRD: Power Down Control
Default value: 0
PWRD = 0
Normal operation (default)
PWRD = 1
Power-down state
This bit is used to enter into low-power mode. Note that PWRD has no reset function.
When this bit is set to 1, the PCM1770 device enters low-power mode and all digital circuits are reset except the
register states, which remain unchanged.
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Analog In/Out
Headphone Output (Stereo)
The PCM1770 and PCM1771 devices have two independent headphone amplifiers, and the amplifier outputs
are provided at the HOUTL and HOUTR terminals. Because the capability of the headphone output is designed for
driving a 16-Ω impedance headphone, less than a 16-Ω impedance headphone is not recommended. A resistor
and a capacitor must be connected to HOUTL and HOUTR to ensure proper output loading.
Monaural Output (BTL Mode/Monaural Speaker)
The monaural output can be created by summing the left and right headphone outputs. When in the BTL mode,
the user must set the headphone output levels to –3 dB using the ATL[5:0] bits in register 01 and the ATR[5:0]
bits in register 02. Moreover, invert the polarity of the right headphone output by using the RINV bit on control
register 03. The RINV bit is recommended to be 0 during the power-up/-down sequence for minimizing audible
pop noise.
Analog Input
The PCM1770 and PCM1771 devices have an analog input, AIN (terminal 10). The AMIX bit (PCM1770) or the
AMIX terminal (PCM1771) allows the user to mix AIN with the headphone outputs (HOUTL and HOUTR) internally.
When in the mixing mode, an ac-coupling capacitor is needed for AIN. But if AIN is not used, AIN must be open
and the AMIX bit (PCM1770) must be disabled or the AMIX terminal (PCM1771) must be low.
Because AIN does not have an internal low-pass filter, it is recommended that the bandwidth of the input signal
into AIN is limited to less than 100 kHz. The source of signals connected to AIN must be connected by low
impedance.
Although the maximum input voltage on AIN is designed to be as large as 0.584 VHP (peak-to-peak), the user
must attenuate the input voltage on AIN and control the digital input data so that each line output (HOUTL and
HOUTR) does not exceed 0.55 VHP (peak-to-peak) in the mixing mode.
VCOM Output
One unbuffered common-mode voltage output terminal, VCOM, is brought out for decoupling purposes. This
terminal is nominally biased to a dc voltage level equal to 0.5 VHP and connected to a 10-µF capacitor. In the
case of a capacitor smaller than 10 µF, pop noise can be generated during the power-on/-off or power-up/-down
sequences.
28
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APPLICATION INFORMATION
Connection Diagrams
Figure 29 shows the basic connection diagram with the necessary power supply bypassing and decoupling
components. It is recommended that the component values shown in Figure 29 be used for all designs.
The use of series resistors (22 Ω to 100 Ω) is recommended for the SCKI, LRCK, BCK, and DATA inputs. The
series resistor combines with the stray PCB and device input capacitance to form a low-pass filter that reduces
high-frequency noise emissions and helps to dampen glitches and ringing present on the clock and data lines.
Power Supplies and Grounding
The PCM1770 and PCM1771 devices require a 2.4-V typical analog supply for VCC and VHP. These 2.4-V
supplies power the DAC, analog output filter, and other circuits. For best performance, these 2.4-V supplies
must be derived from the analog supply using a linear regulator, as shown in Figure 29.
Figure 29 shows the proper power supply bypassing. The 10-µF capacitors must be tantalum or aluminum
electrolytic, while the 0.1-µF capacitors are ceramic (X7R type is recommended for surface-mount applications).
Short-Circuit Protection
Continuous shorting of HOUTL and HOUTR to GND, to a power supply, or to each other is not permitted, as
protection circuitry for an output short is not implemented in the device. If the possibility of shorting cannot be
eliminated in an application, an 8-Ω or higher series resistor must be added between the phase compensation
circuits of the HOUTx pins and the application circuitry (headphone jack in Figure 29).
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APPLICATION INFORMATION (continued)
1.6 V to 3.6 V
Audio DSP
Controller
10 µF
1
LRCK
SCKI
16
2
DATA
MS
15
3
BCK
MC
14
4
PD
MD
13
VCC
12
PCM1770
5
AGND
6
HGND
VHP
11
7
VCOM
AIN
10
8
HOUTR
HOUTL
0.1 µF
10 µF
0.1 µF
10 µF
Analog In
9
10 µF
220 µF
0.022 µF
16 Ω
220 µF
Headphone
RL = 16 Ω
0.022 µF
16 Ω
S0008-01
Figure 29. Basic Connection Diagram
30
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Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from D Revision (April 2005) to E Revision .................................................................................................... Page
•
•
Changed MCKI to SCKI...................................................................................................................................................... 29
Corrected errors, added recommended parts, and changed incorrect symbols ................................................................ 30
Changes from C Revision (May 2004) to D Revision ..................................................................................................... Page
•
•
•
•
•
•
•
•
Changed data sheet to new format ...................................................................................................................................... 1
Changed value for power-supply voltage ............................................................................................................................. 2
Removed package/ordering information, reformatted, and appended at end of data sheet ................................................ 2
Added new Recommended Operating Conditions table to data sheet................................................................................. 2
Changed page layout for Terminal Function tables.............................................................................................................. 6
Changed page layout of Figure 13 and Figure 14.............................................................................................................. 12
In Figure 22, added arrows to all rising edges of BCK for data formats (2), (3), and (4) ................................................... 18
Added new subsection, Short-Circuit Protection, with information concerning protection of output pins........................... 29
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PACKAGE OPTION ADDENDUM
www.ti.com
10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
PCM1770PW
ACTIVE
TSSOP
PW
16
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1770
PCM1770PWR
ACTIVE
TSSOP
PW
16
2000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1770
PCM1770RGA
ACTIVE
VQFN
RGA
20
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1770
PCM1770RGAR
ACTIVE
VQFN
RGA
20
2000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1770
PCM1771PW
ACTIVE
TSSOP
PW
16
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1771
PCM1771PWR
ACTIVE
TSSOP
PW
16
2000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
0 to 70
1771
PCM1771RGA
ACTIVE
VQFN
RGA
20
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
1771
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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