CIRRUS CS4265_07

CS4265
104 dB, 24-Bit, 192 kHz Stereo Audio CODEC
D/A Features
A/D Features
 Multi-Bit Delta Sigma Modulator
 Multi-Bit Delta Sigma Modulator
 104 dB Dynamic Range
 104 dB Dynamic Range
 -90 dB THD+N
 -95 dB THD+N
 Up to 192 kHz Sampling Rates
 Stereo 2:1 Input Multiplexer
 Single-Ended Analog Architecture
 Programmable Gain Amplifier (PGA)
–
–
 Volume Control with Soft Ramp
–
–
0.5 dB Step Size
Zero Crossing, Click-Free Transitions
 Pseudo-Differential Stereo Line Inputs
®
 Stereo Microphone Inputs
 Popguard Technology
–
Minimizes the Effects of Output Transients
 Filtered Line-Level Outputs
 Selectable Serial Audio Interface Formats
–
–
–
Left-Justified up to 24-bit
I²S up to 24-bit
Right-Justified 16-, 18-, 20-, and 24-bit
 Selectable 50/15 µs De-Emphasis
1.8 V to 5 V
Reset
PCM Serial Interface / Loopback
Register Configuration
I2C Control
Data
Level Translator
Serial
Audio
Output
–
–
+32 dB Gain Stage
Low-Noise Bias Supply
 Up to 192 kHz Sampling Rates
 Selectable Serial Audio Interface Formats
– Left-Justified up to 24-bit
– I²S up to 24-bit
 High-Pass Filter or DC Offset Calibration
3.3 V to 5 V
Volume
Control
Level Translator
Serial
Audio
Input
± 12 dB Gain, 0.5 dB Step Size
Zero Crossing, Click-Free Transitions
Volume
Control
Interpolation
Filter
Multibit
ΔΣ Modulator
Switched Capacitor
DAC and Filter
Multibit
ΔΣ Modulator
Switched Capacitor
DAC and Filter
Left DAC Output
Mute
Control
Transmitter Output
Internal Voltage
Reference
High Pass
Filter
Mute Control
Right DAC Output
IEC60958-3 Transmitter
Low-Latency
Anti-Alias Filter
Multibit
Oversampling
ADC
Low-Latency
Anti-Alias Filter
Multibit
Oversampling
ADC
Copyright © Cirrus Logic, Inc. 2007
(All Rights Reserved)
Microphone Bias
Mic Bias
+32 dB
PGA
MUX
High Pass
Filter
http://www.cirrus.com
Interpolation
Filter
3.3 V to 5 V
PGA
Mic Input
1&2
+32 dB
Stereo
Line Input
AUGUST '07
DS657F2
CS4265
System Features
 Synchronous IEC60958-3 Transmitter









– Up to 192 kHz Sampling Rates
– 75 Ω Drive Capability
Serial Audio Data Input Multiplexer
Internal Digital Loopback
Supports Master or Slave Operation
Mute Output Control
Power-Down Mode
– Available for A/D, D/A, CODEC, Mic
Preamplifier
+3.3 V to +5 V Analog Power Supply
+3.3 V to +5 V Digital Power Supply
Direct Interface with 1.8 V to 5 V Logic Levels
Supports I²C® Control Port Interface
General Description
The CS4265 is a highly integrated stereo audio CODEC. The CS4265 performs stereo analog-to-digital
(A/D) and digital-to-analog (D/A) conversion of up to
24-bit serial values at sample rates up to 192 kHz.
A 2:1 stereo input multiplexer is included for selecting
between line-level or microphone-level inputs. The microphone input path includes a +32 dB gain stage and
a low noise bias voltage supply. The PGA is available
for line or microphone inputs and provides gain or attenuation of ±12 dB in 0.5 dB steps.
The output of the PGA is followed by an advanced 5thorder, multi-bit delta sigma modulator and digital filtering/decimation. Sampled data is transmitted by the
serial audio interface at rates from 4 kHz to 192 kHz in
either Slave or Master Mode.
The D/A converter is based on a 4th-order multi-bit delta
sigma modulator with an ultra-linear low-pass filter and
offers a volume control that operates with a 0.5 dB step
size. It incorporates selectable soft ramp and zero
crossing transition functions to eliminate clicks and
pops.
Standard 50/15 μs de-emphasis is available for a
44.1 kHz sample rate for compatibility with digital audio
programs mastered using the 50/15 μs pre-emphasis
technique.
Integrated level translators allow easy interfacing between the CS4265 and other devices operating over a
wide range of logic levels.
The CS4265 is available in a 32-pin QFN package for
both Commercial (-10° to +70° C) and Automotive (-40°
to +105° C) grade. The CDB4265 is also available for
device evaluation and implementation suggestions.
Please refer to “Ordering Information” on page 56 for
complete details.
2
DS657F2
CS4265
TABLE OF CONTENTS
1. PIN DESCRIPTIONS
.......................................................................................................................... 7
2. CHARACTERISTICS AND SPECIFICATIONS ...................................................................................... 9
SPECIFIED OPERATING CONDITIONS ............................................................................................. 9
ABSOLUTE MAXIMUM RATINGS ....................................................................................................... 9
DAC ANALOG CHARACTERISTICS ................................................................................................. 10
DAC COMBINED INTERPOLATION & ON-CHIP ANALOG FILTER RESPONSE ............................ 11
ADC ANALOG CHARACTERISTICS ................................................................................................. 13
ADC ANALOG CHARACTERISTICS ................................................................................................. 15
ADC DIGITAL FILTER CHARACTERISTICS ..................................................................................... 16
DC ELECTRICAL CHARACTERISTICS ............................................................................................. 17
DIGITAL INTERFACE CHARACTERISTICS ...................................................................................... 18
SWITCHING CHARACTERISTICS - SERIAL AUDIO PORT ............................................................. 19
SWITCHING CHARACTERISTICS - I²C CONTROL PORT ............................................................... 22
3. TYPICAL CONNECTION DIAGRAM ................................................................................................... 23
4. APPLICATIONS ................................................................................................................................... 24
4.1 Recommended Power-Up Sequence ............................................................................................. 24
4.2 System Clocking ............................................................................................................................. 24
4.2.1 Master Clock ......................................................................................................................... 24
4.2.2 Master Mode ......................................................................................................................... 25
4.2.3 Slave Mode ........................................................................................................................... 25
4.3 High-Pass Filter and DC Offset Calibration .................................................................................... 25
4.4 Analog Input Multiplexer, PGA, and Mic Gain ................................................................................ 26
4.5 Input Connections ........................................................................................................................... 26
4.5.1 Pseudo-Differential Input ....................................................................................................... 26
4.6 Output Connections ........................................................................................................................ 27
4.7 Output Transient Control ................................................................................................................ 27
4.7.1 Power-Up .............................................................................................................................. 27
4.7.2 Power-Down .......................................................................................................................... 27
4.7.3 Serial Interface Clock Changes ............................................................................................. 27
4.8 DAC Serial Data Input Multiplexer .................................................................................................. 28
4.9 De-Emphasis Filter ......................................................................................................................... 28
4.10 Internal Digital Loopback .............................................................................................................. 28
4.11 Mute Control ................................................................................................................................. 29
4.12 AES3 Transmitter ......................................................................................................................... 29
4.12.1 TxOut Driver ........................................................................................................................ 29
4.12.2 Mono Mode Operation ......................................................................................................... 30
4.13 I²C Control Port Description and Timing ....................................................................................... 30
4.14 Status Reporting ........................................................................................................................... 31
4.15 Reset ............................................................................................................................................ 32
4.16 Synchronization of Multiple Devices ............................................................................................. 32
4.17 Grounding and Power Supply Decoupling .................................................................................... 32
4.18 Package Considerations ............................................................................................................... 32
5. REGISTER QUICK REFERENCE ........................................................................................................ 33
6. REGISTER DESCRIPTION .................................................................................................................. 35
6.1 Chip ID - Register 01h .................................................................................................................... 35
6.2 Power Control - Address 02h ......................................................................................................... 35
6.2.1 Freeze (Bit 7) ......................................................................................................................... 35
6.2.2 Power-Down MIC (Bit 3) ........................................................................................................ 35
6.2.3 Power-Down ADC (Bit 2) ....................................................................................................... 35
6.2.4 Power-Down DAC (Bit 1) ....................................................................................................... 36
6.2.5 Power-Down Device (Bit 0) ................................................................................................... 36
6.3 DAC Control - Address 03h ............................................................................................................ 36
DS657F2
3
CS4265
6.3.1 DAC Digital Interface Format (Bits 5:4) ................................................................................. 36
6.3.2 Mute DAC (Bit 2) ................................................................................................................... 36
6.3.3 De-Emphasis Control (Bit 1) .................................................................................................. 37
6.4 ADC Control - Address 04h ............................................................................................................ 37
6.4.1 Functional Mode (Bits 7:6) .................................................................................................... 37
6.4.2 ADC Digital Interface Format (Bit 4) ...................................................................................... 37
6.4.3 Mute ADC (Bit 2) ................................................................................................................... 38
6.4.4 ADC High-Pass Filter Freeze (Bit 1) ..................................................................................... 38
6.4.5 Master / Slave Mode (Bit 0) ................................................................................................... 38
6.5 MCLK Frequency - Address 05h .................................................................................................... 38
6.5.1 Master Clock Dividers (Bits 6:4) ............................................................................................ 38
6.6 Signal Selection - Address 06h ...................................................................................................... 39
6.6.1 DAC SDIN Source (Bit 7) ...................................................................................................... 39
6.6.2 Digital Loopback (Bit 1) ......................................................................................................... 39
6.7 Channel B PGA Control - Address 07h .......................................................................................... 39
6.7.1 Channel B PGA Gain (Bits 5:0) ............................................................................................. 39
6.8 Channel A PGA Control - Address 08h .......................................................................................... 39
6.8.1 Channel A PGA Gain (Bits 5:0) ............................................................................................. 39
6.9 ADC Input Control - Address 09h ................................................................................................... 40
6.9.1 PGA Soft Ramp or Zero Cross Enable (Bits 4:3) .................................................................. 40
6.9.2 Analog Input Selection (Bit 0) ................................................................................................ 40
6.10 DAC Channel A Volume Control - Address 0Ah ........................................................................... 40
6.11 DAC Channel B Volume Control - Address 0Bh ........................................................................... 41
6.11.1 Volume Control (Bits 7:0) .................................................................................................... 41
6.12 DAC Control 2 - Address 0Ch ...................................................................................................... 41
6.12.1 DAC Soft Ramp or Zero Cross Enable (Bits 7:6) ................................................................ 41
6.12.2 Invert DAC Output (Bit 5) .................................................................................................... 42
6.13 Status - Address 0Dh ................................................................................................................... 42
6.13.1 E to F C-Buffer Transfer ...................................................................................................... 42
6.13.2 Clock Error (Bit 3) ................................................................................................................ 42
6.13.3 ADC Overflow (Bit 1) ........................................................................................................... 42
6.13.4 ADC Underflow (Bit 0) ......................................................................................................... 42
6.14 Status Mask - Address 0Eh .......................................................................................................... 43
6.15 Status Mode MSB - Address 0Fh ................................................................................................. 43
6.16 Status Mode LSB - Address 10h .................................................................................................. 43
6.17 Transmitter Control 1 - Address 11h ............................................................................................ 43
6.17.1 E to F C-Data Buffer Transfer Inhibit (Bit 6) ........................................................................ 43
6.17.2 C-Data Access Mode (Bit 5) ................................................................................................ 43
6.18 Transmitter Control 2 - Address 12h ............................................................................................ 44
6.18.1 Transmitter Digital Interface Format (Bits 7:6) .................................................................... 44
6.18.2 Transmitter Output Driver Control (Bit 5) ............................................................................. 44
6.18.3 Transmitter Mute Control (Bit 4) .......................................................................................... 44
6.18.4 Transmitted Validity Bit Control (Bit 3) ................................................................................ 44
6.18.5 Transmitter Mono/Stereo Operation Control (Bit 2) ............................................................. 44
6.18.6 Mono Mode CS Data Source (Bit 1) .................................................................................... 44
6.18.7 Mono Mode Channel Selection (Bit 0) ................................................................................. 45
7. PARAMETER DEFINITIONS ................................................................................................................ 46
8. DAC FILTER PLOTS
.................................................................................................................... 47
9. ADC FILTER PLOTS ......................................................................................................................... 49
10. EXTERNAL IEC60958-3 TRANSMITTER COMPONENTS ............................................................... 51
10.1 IEC60958-3 Transmitter External Components ............................................................................ 51
10.2 Isolating Transformer Requirements ............................................................................................ 51
11. CHANNEL STATUS BUFFER MANAGEMENT ................................................................................ 52
11.1 IEC60958-3 Channel Status (C) Bit Management ........................................................................ 52
4
DS657F2
CS4265
11.1.1 Accessing the E Buffer ........................................................................................................ 53
11.2 Serial Copy Management System (SCMS) .................................................................................. 53
11.3 Channel Status Data E Buffer Access .......................................................................................... 53
11.3.1 One-Byte Mode ................................................................................................................... 54
11.3.2 Two-Byte Mode ................................................................................................................... 54
12. PACKAGE DIMENSIONS .................................................................................................................. 55
13. THERMAL CHARACTERISTICS AND SPECIFICATIONS ............................................................... 55
14. ORDERING INFORMATION
........................................................................................................ 56
15. REVISION HISTORY .......................................................................................................................... 56
LIST OF FIGURES
Figure 1.DAC Output Test Load ................................................................................................................ 12
Figure 2.Maximum DAC Loading .............................................................................................................. 12
Figure 3.Master Mode Serial Audio Port Timing ....................................................................................... 20
Figure 4.Slave Mode Serial Audio Port Timing ......................................................................................... 20
Figure 5.Format 0, Left-Justified up to 24-Bit Data ................................................................................... 21
Figure 6.Format 1, I²S up to 24-Bit Data ................................................................................................... 21
Figure 7.Format 2, Right-Justified 16-Bit Data.
Format 3, Right-Justified 24-Bit Data. ....................................................................................................... 21
Figure 8.Control Port Timing - I²C Format ................................................................................................. 22
Figure 9.Typical Connection Diagram ....................................................................................................... 23
Figure 10.Master Mode Clocking .............................................................................................................. 25
Figure 11.Analog Input Architecture .......................................................................................................... 26
Figure 12.Pseudo-Differential Input Stage ................................................................................................ 27
Figure 13.De-Emphasis Curve .................................................................................................................. 28
Figure 14.Suggested Active-Low Mute Circuit .......................................................................................... 29
Figure 15.Control Port Timing, I²C Write ................................................................................................... 31
Figure 16.Control Port Timing, I²C Read ................................................................................................... 31
Figure 17.De-Emphasis Curve .................................................................................................................. 37
Figure 18.DAC Single-Speed Stopband Rejection ................................................................................... 47
Figure 19.DAC Single-Speed Transition Band .......................................................................................... 47
Figure 20.DAC Single-Speed Transition Band .......................................................................................... 47
Figure 21.DAC Single-Speed Passband Ripple ........................................................................................ 47
Figure 22.DAC Double-Speed Stopband Rejection .................................................................................. 47
Figure 23.DAC Double-Speed Transition Band ........................................................................................ 47
Figure 24.DAC Double-Speed Transition Band ........................................................................................ 48
Figure 25.DAC Double-Speed Passband Ripple ...................................................................................... 48
Figure 26.DAC Quad-Speed Stopband Rejection ..................................................................................... 48
Figure 27.DAC Quad-Speed Transition Band ........................................................................................... 48
Figure 28.DAC Quad-Speed Transition Band ........................................................................................... 48
Figure 29.DAC Quad-Speed Passband Ripple ......................................................................................... 48
Figure 30.ADC Single-Speed Stopband Rejection ................................................................................... 49
Figure 31.ADC Single-Speed Stopband Rejection ................................................................................... 49
Figure 32.ADC Single-Speed Transition Band (Detail) ............................................................................. 49
Figure 33.ADC Single-Speed Passband Ripple ........................................................................................ 49
Figure 34.ADC Double-Speed Stopband Rejection .................................................................................. 49
Figure 35.ADC Double-Speed Stopband Rejection .................................................................................. 49
Figure 36.ADC Double-Speed Transition Band (Detail) ............................................................................ 50
Figure 37.ADC Double-Speed Passband Ripple ...................................................................................... 50
Figure 38.ADC Quad-Speed Stopband Rejection ..................................................................................... 50
Figure 39.ADC Quad-Speed Stopband Rejection ..................................................................................... 50
Figure 40.ADC Quad-Speed Transition Band (Detail) .............................................................................. 50
Figure 41.ADC Quad-Speed Passband Ripple ......................................................................................... 50
DS657F2
5
CS4265
Figure 42.Consumer Output Circuit (VD = 5 V) ........................................................................................ 51
Figure 43.TTL/CMOS Output Circuit ......................................................................................................... 51
Figure 44.Channel Status Data Buffer Structure ....................................................................................... 52
Figure 45.Flowchart for Writing the E Buffer ............................................................................................. 53
LIST OF TABLES
Table 1. Speed Modes .............................................................................................................................. 24
Table 2. Common Clock Frequencies ....................................................................................................... 24
Table 3. Slave Mode Serial Bit Clock Ratios ............................................................................................. 25
Table 4. Device Revision .......................................................................................................................... 35
Table 5. Freeze-able Bits .......................................................................................................................... 35
Table 6. DAC Digital Interface Formats .................................................................................................... 36
Table 7. De-Emphasis Control .................................................................................................................. 37
Table 8. Functional Mode Selection .......................................................................................................... 37
Table 9. ADC Digital Interface Formats .................................................................................................... 38
Table 10. MCLK Frequency ...................................................................................................................... 38
Table 11. DAC SDIN Source Selection ..................................................................................................... 39
Table 12. Example Gain and Attenuation Settings ................................................................................... 39
Table 13. PGA Soft Cross or Zero Cross Mode Selection ........................................................................ 40
Table 14. Analog Input Selection .............................................................................................................. 40
Table 15. Digital Volume Control Example Settings ................................................................................. 41
Table 16. DAC Soft Cross or Zero Cross Mode Selection ........................................................................ 42
Table 17. Transmitter Digital Interface Formats ........................................................................................ 44
6
DS657F2
CS4265
TXOUT
VD
DGND
MCLK
LRCK
SCLK
SDOUT
SDIN1
1. PIN DESCRIPTIONS
32
31
30
29
28
27
26
25
SDA
1
24
SDIN2
SCL
2
23
TXSDIN
VLC
3
22
VLS
RESET
4
21
MUTEC
VA
5
20
AOUTB
AGND
6
19
AOUTA
AINA
7
18
AGND
AINB
8
17
VA
Thermal Pad
9
10
11
12
13
14
15
16
SGND
AFILTA
AFILTB
VQ
FILT+
MICIN1
MICIN2
MICBIAS
Top-Down (Through Package) View
32-Pin QFN Package
Pin Name
#
Pin Description
SDA
1
Serial Control Data (Input/Output) - Bidirectional data line for the I²C control port.
SCL
2
Serial Control Port Clock (Input) - Serial clock for the I²C control port.
3
Control Port Power (Input) - Determines the required signal level for the control port interface. Refer to
the Recommended Operating Conditions for appropriate voltages.
RESET
4
Reset (Input) - The device enters a low-power mode when this pin is driven low.
VA
5
Analog Power (Input) - Positive power for the internal analog section.
AGND
6
Analog Ground (Input) - Ground reference for the internal analog section.
AINA
AINB
7,
8
Analog Input (Input) - The full-scale level is specified in the ADC Analog Characteristics specification
table.
SGND
9
Signal Ground (Input) - Ground reference for the analog line inputs.
AFILTA
AFILTB
10,
11
Antialias Filter Connection (Output) - Antialias filter connection for the ADC inputs.
VQ
12
Quiescent Voltage (Output) - Filter connection for internal quiescent voltage.
FILT+
13
Positive Voltage Reference (Output) - Positive reference voltage for the internal sampling circuits.
MICIN1
MICIN2
14,
15
Microphone Input (Input) - The full-scale level is specified in the ADC Analog Characteristics specification table.
16
Microphone Bias (Output) - Low noise bias supply for external microphone. Electrical characteristics
are specified in the DC Electrical Characteristics table.
VLC
MICBIAS
DS657F2
7
CS4265
VA
17
Analog Power (Input) - Positive power for the internal analog section.
AGND
18
Analog Ground (Input) - Ground reference for the internal analog section.
AOUTA
AOUTB
MUTEC
VLS
TXSDIN
19, 20 Analog Audio Output (Output) - The full scale output level is specified in the DAC Analog Characteristics specification table.
21
Mute Control (Output) - This pin is active during power-up initialization, reset, muting, when master
clock left/right clock frequency ratio is incorrect, or power-down.
22
Serial Audio Interface Power (Input) - Determines the required signal level for the serial audio interface. Refer to the Recommended Operating Conditions for appropriate voltages.
23
Transmitter Serial Audio Data Input (Input) - Input for two’s complement serial audio data.
SDIN2
24
Serial Audio Data Input 2 (Input) - Input for two’s complement serial audio data.
SDIN1
25
Serial Audio Data Input 1 (Input) - Input for two’s complement serial audio data.
SDOUT
26
Serial Audio Data Output (Output) - Output for two’s complement serial audio data.
SCLK
27
Serial Clock (Input/Output) - Serial clock for the serial audio interface.
28
Left Right Clock (Input/Output) - Determines which channel, Left or Right, is currently active on the
serial audio data line.
MCLK
29
Master Clock (Input) - Clock source for the delta-sigma modulators.
DGND
30
Digital Ground (Input) - Ground reference for the internal digital section.
VD
31
Digital Power (Input) - Positive power for the internal digital section.
TXOUT
32
Transmitter Line Driver Output (Output) - IEC60958-3 driver output.
LRCK
Thermal Pad
8
-
Thermal Pad - Thermal relief pad for optimized heat dissipation.
DS657F2
CS4265
2. CHARACTERISTICS AND SPECIFICATIONS
SPECIFIED OPERATING CONDITIONS
AGND = DGND = 0 V; All voltages with respect to ground.
Parameters
Symbol
Min
Nom
Max
Units
Analog
Digital
Logic - Serial Port
Logic - Control Port
Ambient Operating Temperature (Power Applied)
Commercial
Automotive
VA
VD
VLS
VLC
TA
TA
3.13
3.13
1.71
1.71
-10
-40
5.0
3.3
3.3
3.3
-
5.25
(Note 1)
5.25
5.25
+70
+105
V
V
V
V
°C
°C
DC Power Supplies:
Notes:
1. Maximum of VA+0.25 V or 5.25 V, whichever is less.
ABSOLUTE MAXIMUM RATINGS
AGND = DGND = 0 V All voltages with respect to ground. (Note 2)
Parameter
DC Power Supplies:
Input Current
Analog
Digital
Logic - Serial Port
Logic - Control Port
(Note 3)
Analog Input Voltage
Symbol
Min
Max
Units
VA
VD
VLS
VLC
Iin
-0.3
-0.3
-0.3
-0.3
+6.0
+6.0
+6.0
+6.0
V
V
V
V
-
±10
mA
VINA
AGND-0.3
VA+0.3
V
VIND-S
VIND-C
-0.3
-0.3
VLS+0.3
VLC+0.3
V
V
Ambient Operating Temperature (Power Applied)
TA
-50
+125
°C
Storage Temperature
Tstg
-65
+150
°C
Digital Input Voltage
Logic - Serial Port
Logic - Control Port
2. Operation beyond these limits may result in permanent damage to the device.
Normal operation is not guaranteed at these extremes.
3. Any pin except supplies. Transient currents of up to ±100 mA on the analog input pins will not cause
SCR latch-up.
DS657F2
9
CS4265
DAC ANALOG CHARACTERISTICS
Test Conditions (unless otherwise specified): AGND = DGND = 0 V; VA = 3.13 V to 5.25 V; VD = 3.13 V to 5.25 V
or VA + 0.25 V, whichever is less; VLS = VLC = 1.71 V to 5.25 V; TA = -10° to +70° C for Commercial or -40° to
+85° C for Automotive; Output test signal: 997 Hz full-scale sine wave; Test load RL = 3 kΩ, CL = 10 pF (see
Figure 1), Fs = 48/96/192 kHz. Measurement Bandwidth 10 Hz to 20 kHz; All Connections as shown in Figure 9 on
page 23.
Commercial Grade
Parameter
Symbol
Automotive Grade
Min
Typ
Max
Min
Typ
Max
Unit
98
95
90
87
104
101
96
93
-
96
93
88
85
104
101
96
93
-
dB
dB
dB
dB
-
-90
-81
-41
-93
-73
-33
-84
-87
-
-
-90
-81
-41
-93
-73
-33
-82
-85
-
dB
dB
dB
dB
dB
dB
95
92
88
85
101
98
93
90
-
93
90
86
83
101
98
93
90
-
dB
dB
dB
dB
-
-87
-78
-38
-90
-70
-30
-79
-82
-
-
-87
-78
-38
-90
-70
-30
-77
-80
-
dB
dB
dB
dB
dB
dB
-
100
-
-
100
-
dB
Interchannel Gain Mismatch
-
0.1
0.25
-
0.1
0.25
dB
Gain Drift
-
100
-
-
100
-
ppm/°C
Dynamic Performance for VA = 4.75 V to 5.25 V
Dynamic Range
18 to 24-Bit
16-Bit
(Note 4)
A-Weighted
unweighted
A-Weighted
unweighted
Total Harmonic Distortion + Noise
18 to 24-Bit
(Note 4)
0 dB
-20 dB
-60 dB THD+N
0 dB
-20 dB
-60 dB
16-Bit
Dynamic Performance for VA = 3.13 V to 3.46 V
Dynamic Range
18 to 24-Bit
16-Bit
(Note 4)
A-Weighted
unweighted
A-Weighted
unweighted
Total Harmonic Distortion + Noise
18 to 24-Bit
16-Bit
Interchannel Isolation
(Note 4)
0 dB
-20 dB
-60 dB THD+N
0 dB
-20 dB
-60 dB
(1 kHz)
DC Accuracy
Analog Output
Full Scale Output Voltage
0.60*VA 0.65*VA 0.70*VA 0.60*VA 0.65*VA 0.70*VA
Vpp
DC Current draw from an AOUT pin
(Note 5)
IOUT
-
-
10
-
-
10
μA
AC-Load Resistance
(Note 6)
RL
3
-
-
3
-
-
kΩ
Load Capacitance
(Note 6)
CL
-
-
100
-
-
100
pF
ZOUT
-
150
-
-
150
-
Ω
Output Impedance
4. One-half LSB of triangular PDF dither added to data.
5. Guaranteed by design. The DC current draw represents the allowed current draw from the AOUT pin
due to typical leakage through the electrolytic DC blocking capacitors.
10
DS657F2
CS4265
6. Guaranteed by design. See Figure 2. RL and CL reflect the recommended minimum resistance and
maximum capacitance required for the internal op-amp’s stability. CL affects the dominant pole of the
internal output amp; increasing CL beyond 100 pF can cause the internal op-amp to become unstable.
DAC COMBINED INTERPOLATION & ON-CHIP ANALOG FILTER RESPONSE
Parameter (Note 7,10)
Symbol
Combined Digital and On-chip Analog Filter Response
Passband (Note 7)
Min
Typ
Max
Unit
Single-Speed Mode
to -0.1 dB corner
to -3 dB corner
0
0
-
0.35
0.4992
Fs
Fs
Frequency Response 10 Hz to 20 kHz
-0.175
-
+0.01
dB
StopBand
0.5465
-
-
Fs
50
-
-
dB
-
10/Fs
-
s
-
-
+0.05/-0.25
dB
StopBand Attenuation
(Note 8)
Group Delay
De-emphasis Error (Note 9)
tgd
Fs = 44.1 kHz
Combined Digital and On-chip Analog Filter Response
Passband (Note 7)
Double-Speed Mode
to -0.1 dB corner
to -3 dB corner
Frequency Response 10 Hz to 20 kHz
StopBand
StopBand Attenuation
(Note 8)
Group Delay
tgd
0
0
-
0.22
0.501
Fs
Fs
-0.15
-
+0.15
dB
0.5770
-
-
Fs
55
-
-
dB
-
5/Fs
-
s
Combined Digital and On-chip Analog Filter Response
Quad-Speed Mode
Passband (Note 7)
0
0
-
0.110
0.469
Fs
Fs
-0.12
-
0
dB
0.7
-
-
Fs
51
-
-
dB
-
2.5/Fs
-
s
to -0.1 dB corner
to -3 dB corner
Frequency Response 10 Hz to 20 kHz
StopBand
StopBand Attenuation
(Note 8)
Group Delay
tgd
7. Filter response is guaranteed by design.
8. For Single-Speed Mode, the Measurement Bandwidth is 0.5465 Fs to 3 Fs.
For Double-Speed Mode, the Measurement Bandwidth is 0.577 Fs to 1.4 Fs.
For Quad-Speed Mode, the Measurement Bandwidth is 0.7 Fs to 1 Fs.
9. De-emphasis is available only in Single-Speed Mode.
10. Response is clock dependent and will scale with Fs. Note that the amplitude vs. frequency plots of this
data (Figures 18 to 27) have been normalized to Fs and can be de-normalized by multiplying the X-axis
scale by Fs.
DS657F2
11
CS4265
3.3 µF
V
out
AOUTx
R
L
AGND
C
L
Capacitive Load -- C L (pF)
125
100
75
25
2.5
3
Figure 1. DAC Output Test Load
12
Safe Operating
Region
50
5
10
15
20
Resistive Load -- RL (kΩ )
Figure 2. Maximum DAC Loading
DS657F2
CS4265
ADC ANALOG CHARACTERISTICS
Test conditions (unless otherwise specified): AGND = DGND = 0 V; VA = 3.13 V to 5.25 V; VD = 3.13 V to 5.25 V
or VA + 0.25 V, whichever is less; VLS = VLC = 1.71 V to 5.25 V; TA = -10° to +70° C for Commercial or -40° to
+85° C for Automotive; Input test signal: 1 kHz sine wave; measurement bandwidth is 10 Hz to 20 kHz;
Fs = 48/96/192 kHz.; All connections as shown in Figure 9 on page 23.
Line-Level Inputs
Commercial Grade
Parameter
Symbol
Dynamic Performance for VA = 4.75 V to 5.25 V
Automotive Grade
Min
Typ
Max
Min
Typ
Max
Unit
98
95
-
104
101
98
-
96
93
-
104
101
98
-
dB
dB
dB
92
89
-
98
95
92
-
90
87
-
98
95
92
-
dB
dB
dB
-
-95
-81
-41
-92
-89
-
-
-95
-81
-41
-92
-87
-
dB
dB
dB
dB
-
-92
-75
-35
-89
-86
-
-
-92
-75
-35
-89
-84
-
dB
dB
dB
dB
93
90
-
101
98
95
-
91
88
-
101
98
95
-
dB
dB
dB
89
86
-
95
92
89
-
87
84
-
95
92
89
-
dB
dB
dB
-
-92
-78
-38
-84
-86
-
-
-92
-78
-38
-84
-84
-
dB
dB
dB
dB
-
-89
-72
-32
-81
-83
-
-
-89
-72
-32
-81
-81
-
dB
dB
dB
dB
Dynamic Range
(Note 13)
(Note 13)
PGA Setting: -12 dB to +6 dB
A-weighted
unweighted
40 kHz bandwidth unweighted
PGA Setting: +12 dB Gain
A-weighted
unweighted
40 kHz bandwidth unweighted
Total Harmonic Distortion + Noise
(Note 12)
PGA Setting: -12 dB to +6 dB
-1 dB
-20 dB
-60 dB
(Note 13)
40 kHz bandwidth
-1 dB THD+N
PGA Setting: +12 dB Gain
-1 dB
-20 dB
-60 dB
(Note 13)
40 kHz bandwidth
-1 dB
Dynamic Performance for VA = 3.13 V to 3.46 V
Dynamic Range
(Note 13)
(Note 13)
PGA Setting: -12 dB to +6 dB
A-weighted
unweighted
40 kHz bandwidth unweighted
PGA Setting: +12 dB Gain
A-weighted
unweighted
40 kHz bandwidth unweighted
Total Harmonic Distortion + Noise
(Note 12)
PGA Setting: -12 dB to +6 dB
-1 dB
-20 dB
-60 dB
(Note 13)
40 kHz bandwidth
-1 dB THD+N
PGA Setting: +12 dB Gain
-1 dB
-20 dB
-60 dB
(Note 13)
40 kHz bandwidth
-1 dB
DS657F2
13
CS4265
Line-Level Inputs
Commercial Grade
Parameter
Symbol
Automotive Grade
Min
Typ
Max
Min
Typ
Max
Unit
-
90
-
-
90
-
dB
-
±100
-
±10
-
-
±100
-
±10
-
%
ppm/°C
Interchannel Isolation
DC Accuracy
Gain Error
Gain Drift
Line-Level Input Characteristics
Full-scale Input Voltage
Input Impedance
(Note 11)
Maximum Interchannel Input Impedance
Mismatch
0.51*VA 0.57*VA 0.63*VA 0.51*VA 0.57*VA 0.63*VA
6.12
6.8
7.48
5.44
6.8
8.16
-
5
-
-
5
-
Vpp
kΩ
%
Line-Level and Microphone-Level Inputs
Commercial Grade
Parameter
Symbol
Automotive Grade
Min
Typ
Max
Min
Typ
Max
Unit
-
0.1
-
-
0.1
-
dB
-
0.5
-
0.4
-
0.5
-
0.4
dB
dB
DC Accuracy
Interchannel Gain Mismatch
Programmable Gain Characteristics
Gain Step Size
Absolute Gain Step Error
11. Valid when the line-level inputs are selected.
14
DS657F2
CS4265
ADC ANALOG CHARACTERISTICS
(Continued)
Microphone-Level Inputs
Commercial Grade
Parameter
Symbol
Dynamic Performance for VA = 4.75 V to 5.25 V
Automotive Grade
Min
Typ
Max
Min
Typ
Max
Unit
77
74
83
80
-
75
72
83
80
-
dB
dB
65
62
71
68
-
63
60
71
68
-
dB
dB
-
-80
-60
-20
-74
-
-
-80
-60
-20
-72
-
dB
dB
dB
-
-68
-
-
-68
-
dB
77
74
83
80
-
75
72
83
80
-
dB
dB
65
62
71
68
-
63
60
71
68
-
dB
dB
-
-80
-60
-20
-74
-
-
-80
-60
-20
-72
-
dB
dB
dB
-
-68
80
-
-
-68
80
-
dB
dB
-
±300
±5
-
-
±300
±5
-
%
ppm/°C
Dynamic Range
PGA Setting: -12 dB to 0 dB
A-weighted
unweighted
PGA Setting: +12 dB
A-weighted
unweighted
Total Harmonic Distortion + Noise
(Note 12)
PGA Setting: -12 dB to 0 dB
-1 dB
-20 dB
THD+N
-60 dB
PGA Setting: +12 dB
-1 dB
Dynamic Performance for VA = 3.13 V to 3.46 V
Dynamic Range
PGA Setting: -12 dB to 0 dB
A-weighted
unweighted
PGA Setting: +12 dB
A-weighted
unweighted
Total Harmonic Distortion + Noise
(Note 12)
PGA Setting: -12 dB to 0 dB
-1 dB
-20 dB
THD+N
-60 dB
PGA Setting: +12 dB
-1 dB
Interchannel Isolation
DC Accuracy
Gain Error
Gain Drift
Microphone-Level Input Characteristics
Full-scale Input Voltage
Input Impedance
(Note 14)
0.013*VA 0.017*VA 0.021*VA 0.013*VA 0.017*VA 0.021*VA
60
60
-
Vpp
kΩ
12. Referred to the typical line-level full-scale input voltage
13. Valid for Double- and Quad-Speed Modes only.
14. Valid when the microphone-level inputs are selected.
DS657F2
15
CS4265
ADC DIGITAL FILTER CHARACTERISTICS
Parameter (Notes 15, 17)
Symbol
Min
Typ
Max
Unit
0
-
0.4896
Fs
-
-
0.035
dB
0.5688
-
-
Fs
70
-
-
dB
-
12/Fs
-
s
0
-
0.4896
Fs
-
-
0.025
dB
Single-Speed Mode
Passband
(-0.1 dB)
Passband Ripple
Stopband
Stopband Attenuation
Total Group Delay (Fs = Output Sample Rate)
tgd
Double-Speed Mode
Passband
(-0.1 dB)
Passband Ripple
Stopband
Stopband Attenuation
Total Group Delay (Fs = Output Sample Rate)
tgd
0.5604
-
-
Fs
69
-
-
dB
-
9/Fs
-
s
0
-
0.2604
Fs
-
-
0.025
dB
Quad-Speed Mode
Passband
(-0.1 dB)
Passband Ripple
Stopband
Stopband Attenuation
Total Group Delay (Fs = Output Sample Rate)
tgd
0.5000
-
-
Fs
60
-
-
dB
-
5/Fs
-
s
-
1
20
-
Hz
Hz
-
10
-
Deg
-
0
dB
High-Pass Filter Characteristics
Frequency Response
Phase Deviation
-3.0 dB
-0.13 dB
(Note 16)
@ 20 Hz
(Note 16)
Passband Ripple
Filter Settling Time
-
105/Fs
s
15. Filter response is guaranteed by design.
16. Response shown is for Fs = 48 kHz.
17. Response is clock-dependent and will scale with Fs. Note that the response plots (Figures 30 to 41) are
normalized to Fs and can be de-normalized by multiplying the X-axis scale by Fs.
16
DS657F2
CS4265
DC ELECTRICAL CHARACTERISTICS
AGND = DGND = 0 V, all voltages with respect to ground. MCLK=12.288 MHz; Fs=48 kHz; Master Mode.
Parameter
Symbol
Min
Typ
Max
Unit
V
V
V
V
IA
IA
ID
ID
-
41
37
39
23
50
45
47
28
mA
mA
mA
mA
VA = 5 V
VLS, VLC, VD=5 V
IA
ID
-
0.50
0.54
-
mA
mA
Power Consumption
(Normal Operation)
VA, VD, VLS, VLC = 5 V
(Power-Down Mode)
VA, VD, VLS, VLC = 3.3 V
VA, VD, VLS, VLC = 5 V
-
-
400
198
4.2
485
241
-
mW
mW
mW
PSRR
-
55
-
dB
VQ
-
0.5 x VA
-
VDC
IQ
-
-
1
μA
ZQ
-
4.5
-
kΩ
Power Supply Current
(Normal Operation)
VA = 5
VA = 3.3
VD, VLS, VLC = 5
VD, VLS, VLC = 3.3
Power Supply Current
(Power-Down Mode) (Note 18)
Power Supply Rejection Ratio (1 kHz)
(Note 19)
VQ Characteristics
Quiescent Voltage
DC Current from VQ
VQ Output Impedance
FILT+ Nominal Voltage
Microphone Bias Voltage
Current from MICBIAS
(Note 20)
FILT+
-
VA
-
VDC
MICBIAS
-
0.8 x VA
-
VDC
IMB
-
-
2
mA
18. Power-Down Mode is defines as RESET = Low with all clock and data lines held static and no analog
input.
19. Valid with the recommended capacitor values on FILT+ and VQ as shown in the Typical Connection
Diagram.
20. Guaranteed by design. The DC current draw represents the allowed current draw due to typical leakage
through the electrolytic de-coupling capacitors.
DS657F2
17
CS4265
DIGITAL INTERFACE CHARACTERISTICS
Test conditions (unless otherwise specified): AGND = DGND = 0 V; VLS = VLC = 1.71 V to 5.25 V.
Parameters (Note 21)
Symbol
Min
Typ
Max
Units
VIH
VIH
VIH
VIH
VIL
VIL
VOH
VOH
VOH
VOH
VOL
VOL
VOL
VOL
Iin
0.8xVLS
0.8xVLC
0.7xVLS
0.7xVLC
VLS-1.0
VLC-1.0
VA-1.0
VD-1.0
-
3
0.2xVLS
0.2xVLC
0.4
0.4
0.4
0.4
±10
1
-
V
V
V
V
V
V
V
V
V
V
V
V
V
V
μA
pF
mA
High-Level Input Voltage
VL = 1.71 V
VL > 2.0 V
Low-Level Input Voltage
High-Level Output Voltage at Io = 2 mA
Low-Level Output Voltage at Io = 2 mA
Input Leakage Current
Input Capacitance
Maximum MUTEC Drive Current
Serial Port
Control Port
Serial Port
Control Port
Serial Port
Control Port
Serial Port
Control Port
MUTEC
TXOUT
Serial Port
Control Port
MUTEC
TXOUT
(Note 22)
21. Serial Port signals include: MCLK, SCLK, LRCK, SDIN1, SDIN2, TXSDIN, SDOUT.
Control Port signals include: SCL, SDA, RESET.
22. Guaranteed by design.
18
DS657F2
CS4265
SWITCHING CHARACTERISTICS - SERIAL AUDIO PORT
Logic ‘0’ = DGND = AGND = 0 V; Logic ‘1’ = VL, CL = 20 pF. (Note 23)
Parameter
Sample Rate
Single-Speed Mode
Double-Speed Mode
Quad-Speed Mode
Symbol
Min
Typ
Max
Unit
Fs
Fs
Fs
4
50
100
-
50
100
200
kHz
kHz
kHz
fmclk
tclkhl
1.024
8
45
50
51.200
55
MHz
ns
%
-10
0
16
20
50
50
-
10
36
-
%
%
ns
ns
ns
ns
40
50
60
%
-
-
ns
-
-
ns
MCLK Specifications
MCLK Frequency
MCLK Input Pulse Width High/Low
MCLK Output Duty Cycle
Master Mode
LRCK Duty Cycle
SCLK Duty Cycle
SCLK falling to LRCK edge
SCLK falling to SDOUT valid
SDIN valid to SCLK rising setup time
SCLK rising to SDIN hold time
tslr
tsdo
tsdis
tsdih
Slave Mode
LRCK Duty Cycle
SCLK Period
9
Single-Speed Mode
tsclkw
10
--------------------( 128 )Fs
Double-Speed Mode
tsclkw
10
-----------------( 64 )Fs
Quad-Speed Mode
tsclkw
10
-----------------( 64 )Fs
-
-
ns
tsclkh
tsclkl
tslr
tsdo
tsdis
tsdih
30
48
-10
0
16
20
-
10
36
-
ns
ns
ns
ns
ns
ns
9
9
SCLK Pulse Width High
SCLK Pulse Width Low
SCLK falling to LRCK edge
SCLK falling to SDOUT valid
SDIN valid to SCLK rising setup time
SCLK rising to SDIN hold time
23. See Figures 3 and 4 on page 20.
DS657F2
19
CS4265
LRCK
O utput
t
slr
SCLK
O utput
t
sdo
SDO UT
t
t
sdis
sdih
SDIN
Figure 3. Master Mode Serial Audio Port Timing
LRCK
Input
t
t
sclkh
slr
t
sclkl
SCLK
Input
t
t
sdo
sclkw
SDOUT
t
sdis
t
sdih
SDIN
Figure 4. Slave Mode Serial Audio Port Timing
20
DS657F2
CS4265
Channel B - Right
Channel A - Left
LRCK
SCLK
SDATA
MSB -1
-2
-3
-4
-5
+5 +4
+3 +2
+1 LSB
MSB -1
-2
-3
+5
-4
+4 +3
+2 +1 LSB
Figure 5. Format 0, Left-Justified up to 24-Bit Data
Channel A - Left
LRCK
Channel B - Right
SCLK
SDATA
MSB -1
-2
-3
-4
-5
+5 +4 +3 +2 +1 LSB
MSB -1
-2
-3
+5 +4 +3 +2 +1 LSB
-4
Figure 6. Format 1, I²S up to 24-Bit Data
LRCK
Channel B - Right
Channel A - Left
SCLK
SDATA
LSB
MSB -1
-2 -3 -4 -5 -6
+6 +5 +4 +3 +2 +1 LSB
MSB -1
-2 -3 -4 -5 -6
+6 +5 +4 +3 +2 +1 LSB
Figure 7. Format 2, Right-Justified 16-Bit Data.
Format 3, Right-Justified 24-Bit Data.
DS657F2
21
CS4265
SWITCHING CHARACTERISTICS - I²C CONTROL PORT
Inputs: Logic 0 = DGND = AGND = 0 V, Logic 1 = VLC, CL = 30 pF.
Parameter
Symbol
Min
Max
Unit
SCL Clock Frequency
fscl
-
100
kHz
RESET Rising Edge to Start
tirs
500
-
ns
Bus Free Time Between Transmissions
tbuf
4.7
-
µs
Start Condition Hold Time (prior to first clock pulse)
thdst
4.0
-
µs
Clock Low time
tlow
4.7
-
µs
Clock High Time
thigh
4.0
-
µs
tsust
4.7
-
µs
thdd
0
-
µs
tsud
250
-
ns
-
1
µs
Setup Time for Repeated Start Condition
SDA Hold Time from SCL Falling
(Note 24)
SDA Setup time to SCL Rising
Rise Time of SCL and SDA
(Note 25)
trc, trd
Fall Time SCL and SDA
(Note 25)
tfc, tfd
-
300
ns
Setup Time for Stop Condition
tsusp
4.7
-
µs
Acknowledge Delay from SCL Falling
tack
300
1000
ns
24. Data must be held for sufficient time to bridge the transition time, tfc, of SCL.
25. Guaranteed by design.
RST
t
irs
Stop
R e p e ate d
Sta rt
Sta rt
t rd
t fd
Stop
SDA
t
buf
t
t
hdst
t
high
t fc
hdst
t susp
SCL
t
lo w
t
hdd
t sud
t ack
t sust
t rc
Figure 8. Control Port Timing - I²C Format
22
DS657F2
CS4265
3. TYPICAL CONNECTION DIAGRAM
+3.3V to +5V
10 µF
0.1 µF
0.1 µF
VD
+1.8V
to +5V
VA
0.1 µF
VA
Mute
Drive
MUTEC
VLS
3.3 µF
47 kΩ
Note 4
SDIN1
10 kΩ
*
C
10 kΩ
*
C
TXSDIN
Note 2 :
CS4265
For best response to Fs/2 :
C=
Rext + 470
4πFs(Rext × 470)
This circuitry is intended for applications where the CS4265
connects directly to an unbalanced output of the design . For internal
routing applications please see the DAC Analog Output
Characteristics section for loading limitations.
LRCK
10 µF
AIN1A
TXOUT
10 µF
100 Ω
Left Analog Input 1
* 1800 pF
100 kΩ
* 1800 pF
100 kΩ
SGND
Signal Ground
AIN1B
RST
MicroController
10 µF
SCL
Right Analog Input 1
100 Ω
10 µF
MICIN1
SDA
Microphone Input 1
Microphone Input 2
MICIN2
2 kΩ
+1.8V
to +5V
10 µF
2 kΩ
Note 1
RL
VLC
RL
Note 3
MICBIAS
0.1 µF
FILT+
AGND
AGND
Note 1: Resistors are required for I²C control
port operation
Note 3: The value of RL is dictated by the
microphone carteridge.
Note 4: Sets the LSB of the 7-bit chip address.
See the I²C Control Port Description and
Timing section.
Rext
470Ω
3.3 µF
SCLK
Digital Audio
Output
Rext
Optional
Analog
Muting
AOUTB
SDIN2
MCLK
See Note 2
470Ω
AOUTA
SDOUT
Digital Audio
Processor
+3.3V to +5V
0.1 µF 10 µF
AFILTA
AFILTB
VQ
DGND
*
0.1 µF
47 µF
*
2.2nF
2.2nF
10 µF
0.1 µF
10 µF
* Capacitors must be C0G or equivalent
Figure 9. Typical Connection Diagram
DS657F2
23
CS4265
4. APPLICATIONS
4.1
Recommended Power-Up Sequence
1. Hold RESET low until the power supply,MCLK, and LRCK are stable. In this state, the Control Port is
reset to its default settings.
2. Bring RESET high. The device will remain in a low power state with the PDN bit set by default. The control port will be accessible.
3. The desired register settings can be loaded while the PDN bit remains set.
4. Clear the PDN bit to initiate the power-up sequence.
4.2
System Clocking
The CS4265 will operate at sampling frequencies from 4 kHz to 200 kHz. This range is divided into three
speed modes as shown in Table 1.
Mode
Sampling Frequency
Single-Speed
4-50 kHz
Double-Speed
50-100 kHz
Quad-Speed
100-200 kHz
Table 1. Speed Modes
4.2.1
Master Clock
MCLK/LRCK must maintain an integer ratio as shown in Table 2. The LRCK frequency is equal to Fs, the
frequency at which audio samples for each channel are clocked into or out of the device. The FM bits (See
“Functional Mode (Bits 7:6)” on page 37.) and the MCLK Freq bits (See “MCLK Frequency - Address 05h”
on page 38.) configure the device to generate the proper clocks in Master Mode and receive the proper
clocks in Slave Mode. Table 2 illustrates several standard audio sample rates and the required MCLK and
LRCK frequencies.
LRCK
(kHz)
MCLK (MHz)
64x
96x
128x
192x
256x
384x
512x
768x
1024x
32
-
-
-
-
8.1920
12.2880
16.3840
24.5760
32.7680
44.1
-
-
-
-
11.2896
16.9344
22.5792
33.8680
45.1584
48
-
-
-
-
12.2880
18.4320
24.5760
36.8640
49.1520
64
-
-
8.1920
12.2880
16.3840
24.5760
32.7680
-
-
88.2
-
-
11.2896
16.9344
22.5792
33.8680
45.1584
-
-
96
-
-
12.2880
18.4320
24.5760
36.8640
49.1520
-
-
128
8.1920
12.2880
16.3840
24.5760
32.7680
-
-
-
-
176.4
11.2896
16.9344
22.5792
33.8680
45.1584
-
-
-
-
192
12.2880
18.4320
24.5760
36.8640
49.1520
-
-
-
Mode
QSM
DSM
SSM
Table 2. Common Clock Frequencies
24
DS657F2
CS4265
4.2.2
Master Mode
As a clock master, LRCK and SCLK will operate as outputs. LRCK and SCLK are internally derived from
MCLK with LRCK equal to Fs and SCLK equal to 64 x Fs as shown in Figure 10.
MCLK Freq Bits
MCLK
÷1
000
÷1.5
001
÷2
010
÷3
011
÷4
100
÷256
00
÷128
01
÷64
10
LRCK
FM Bits
÷4
00
÷2
01
÷1
10
SCLK
Figure 10. Master Mode Clocking
4.2.3
Slave Mode
In Slave Mode, SCLK and LRCK operate as inputs. The Left/Right clock signal must be equal to the sample rate, Fs, and must be synchronously derived from the supplied master clock, MCLK.
The serial bit clock, SCLK, must be synchronously derived from the master clock, MCLK, and be equal to
128x, 64x, 48x or 32x Fs, depending on the desired speed mode. Refer to Table 3 for required clock ratios.
SCLK/LRCK Ratio
Single-Speed
Double-Speed
Quad-Speed
32x, 48x, 64x, 128x
32x, 48x, 64x
32x, 48x, 64x
Table 3. Slave Mode Serial Bit Clock Ratios
4.3
High-Pass Filter and DC Offset Calibration
When using operational amplifiers in the input circuitry driving the CS4265, a small DC offset may be driven
into the A/D converter. The CS4265 includes a high-pass filter after the decimator to remove any DC offset
which could result in recording a DC level, possibly yielding clicks when switching between devices in a multichannel system.
The high-pass filter continuously subtracts a measure of the DC offset from the output of the decimation
filter. If the HPFFreeze bit (See “ADC High-Pass Filter Freeze (Bit 1)” on page 38.) is set during normal operation, the current value of the DC offset for the each channel is frozen and this DC offset will continue to
be subtracted from the conversion result. This feature makes it possible to perform a system DC offset calibration by:
1. Running the CS4265 with the high-pass filter enabled until the filter settles. See the ADC Digital Filter
Characteristics section for filter settling time.
2. Disabling the high-pass filter and freezing the stored DC offset.
A system calibration performed in this way will eliminate offsets anywhere in the signal path between the
calibration point and the CS4265.
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CS4265
4.4
Analog Input Multiplexer, PGA, and Mic Gain
The CS4265 contains a stereo 2-to-1 analog input multiplexer followed by a programmable gain amplifier
(PGA). The input multiplexer is able to select either a line-level input source, or a mic-level input source, and
route it to the PGA. The mic-level input passes through a +32 dB gain stage prior to the input multiplexer,
allowing it to be used for microphone-level signals without the need for any external gain. The PGA stage
provides 12 dB of gain or attenuation in 0.5 dB steps. Figure 11 shows the architecture of the input multiplexer, PGA, and mic gain stages.
AINA
MUX
MICIN1
PGA
+32 dB
Analog Input
Selection Bits
Channel A
PGA Gain Bits
Channel B
PGA Gain Bits
AINB
MUX
MICIN2
+32 dB
Out to ADC
Channel A
PGA
Out to ADC
Channel B
Figure 11. Analog Input Architecture
The ““Analog Input Selection (Bit 0)” on page 40” outlines the bit settings necessary to control the input multiplexer and mic gain. “Channel B PGA Control - Address 07h” on page 39 and “Channel A PGA Control Address 08h” on page 39 outline the register settings necessary to control the PGA. By default, the linelevel input is selected by the input multiplexer, and the PGA is set to 0 dB.
4.5
Input Connections
The analog modulator samples the input at 6.144 MHz (MCLK=12.288 MHz). The digital filter will reject signals within the stopband of the filter. However, there is no rejection for input signals which are
(n × 6.144 MHz) the digital passband frequency, where n=0,1,2,... Refer to the Typical Connection Diagram
for the recommended analog input circuit that will attenuate noise energy at 6.144 MHz. The use of capacitors which have a large voltage coefficient (such as general-purpose ceramics) must be avoided since
these can degrade signal linearity. Any unused analog input pairs should be left unconnected.
4.5.1
Pseudo-Differential Input
The CS4265 implements a pseudo-differential input stage. The SGND input is intended to be used as a
pseudo-differential reference signal. This feature allows for common mode noise rejection with singleended signals. Figure 12 shows a basic diagram outlining the internal implementation of the pseudo-differential input stage. The Typical Connection Diagram shows the recommended pseudo-differential input
26
DS657F2
CS4265
topology. If pseudo-differential input functionality is not required, simply connect the SGND pin to AGND
through the parallel combination of a 10 µF and a 0.1 µF capacitor.
CS4265
A IN A
VA
+
In to P G A
10 µF
SGND
0.1 µF
A IN B
+
-
In to P G A
N ote: If pseudo-differential input functionality is not required, the
connections shown with dashed line should be added.
Figure 12. Pseudo-Differential Input Stage
4.6
Output Connections
The CS4265 DACs implement a switched-capacitor filter, followed by a continuous time low-pass filter. Its
response, combined with that of the digital interpolator, is shown in Section 8. “DAC Filter Plots” on
page 47”. The recommended external analog circuitry is shown in the Typical Connection Diagram.
The CS4265 DAC does not include phase or amplitude compensation for an external filter. Therefore, the
DAC system phase and amplitude response is dependent on the external analog circuitry.
4.7
Output Transient Control
The CS4265 uses Popguard® technology to minimize the effects of output transients during power-up and
power-down. This technique eliminates the audio transients commonly produced by single-ended, singlesupply converters when it is implemented with external DC-blocking capacitors connected in series with the
audio outputs. To make best use of this feature, it is necessary to understand its operation.
4.7.1
Power-Up
When the device is initially powered-up, the DAC outputs AOUTA and AOUTB are clamped to VQ, which
is initially low. After the PDN bit is released (set to ‘0’), the outputs begin to ramp with VQ towards the
nominal quiescent voltage. This ramp takes approximately 200 ms to complete. The gradual voltage
ramping allows time for the external DC-blocking capacitors to charge to VQ, effectively blocking the quiescent DC voltage. Audio output will begin after approximately 2000 sample periods.
4.7.2
Power-Down
To prevent audio transients at power-down, the DC-blocking capacitors must fully discharge before turning off the power. In order to do this, either the PDN should be set or the device should be reset about
250 ms before removing power. During this time, the voltage on VQ and the DAC outputs will gradually
discharge to GND. If power is removed before this 250 ms time period has passed, a transient will occur
when the VA supply drops below that of VQ. There is no minimum time for a power cycle; power may be
re-applied at any time.
4.7.3
Serial Interface Clock Changes
When changing the clock ratio or sample rate, it is recommended that zero data (or near zero data) be
present on the selected SDIN pin for at least 10 LRCK samples before the change is made. During the
DS657F2
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CS4265
clocking change, the DAC outputs will always be in a zero-data state. If non-zero serial audio input is
present at the time of switching, a slight click or pop may be heard as the DAC output automatically goes
to its zero-data state.
4.8
DAC Serial Data Input Multiplexer
The CS4265 contains a 2-to-1 serial data input multiplexer. This allows two separate data sources to be
input into the DAC without the use of any external multiplexing components. “Section 6.6.1 “DAC SDIN
Source (Bit 7)” on page 39” describes the control port settings necessary to control the multiplexer.
4.9
De-Emphasis Filter
The CS4265 includes on-chip digital de-emphasis optimized for a sample rate of 44.1 kHz. The filter response is shown in Figure 13. The frequency response of the de-emphasis curve scales proportionally with
changes in sample rate, Fs. Please see Section 6.3.3 “De-Emphasis Control (Bit 1)” on page 37 for de-emphasis control.
The de-emphasis feature is included to accommodate audio recordings that utilize 50/15 μs pre-emphasis
equalization as a means of noise reduction.
De-emphasis is only available in Single-Speed Mode.
Gain
dB
T1=50 µs
0dB
T2 = 15 µs
-10dB
F1
3.183 kHz
F2
Frequency
10.61 kHz
Figure 13. De-Emphasis Curve
4.10
Internal Digital Loopback
The CS4265 supports an internal digital loopback mode in which the output of the ADC is routed to the input
of the DAC. This mode may be activated by setting the LOOP bit in the Signal Selection register (See “Signal
Selection - Address 06h” section on page 39).
When this bit is set, the status of the DAC_DIF[1:0] bits in register 03h will be disregarded by the CS4265.
Any changes made to the DAC_DIF[1:0] bits while the LOOP bit is set will have no impact on operation until
the LOOP bit is cleared, at which time the Digital Interface Format of the DAC will operate according to the
format selected by the DAC_DIF[1:0] bits. While the LOOP bit is set, data will be present on the SDOUT pin
in the format selected by the ADC_DIF bit in register 04h.
28
DS657F2
CS4265
4.11
Mute Control
The MUTEC pin becomes active during power-up initialization, reset, muting, if the MCLK to LRCK ratio is
incorrect, and during power-down. The MUTEC pin is intended to be used as control for an external mute
circuit in order to add off-chip mute capability.
Use of the Mute Control function is not mandatory but recommended for designs requiring the absolute minimum in extraneous clicks and pops. Also, use of the Mute Control function can enable the system designer
to achieve idle channel noise/signal-to-noise ratios which are only limited by the external mute circuit. The
MUTEC pin is an active-low CMOS driver. See Figure 14 for a suggested active-low mute circuit.
+VEE
AC
Couple
AOUT
560 Ω
LPF
Audio
Out
47 kΩ
CS4265
-VEE
+VA
MMUN2111LT1
MUTEC
2 kΩ
10 kΩ
-VEE
Figure 14. Suggested Active-Low Mute Circuit
4.12
AES3 Transmitter
The CS4265 includes an IEC60958-3 digital audio transmitter. A comprehensive buffering scheme provides
write access to the channel status data. This buffering scheme is described in the “Channel Status Buffer
Management” section on page 52.
The IEC60958-3 transmitter encodes and transmits audio and digital data according to the IEC60958-3
(S/PDIF) interface standard. The transmitter receives audio data from the input pin TXSDIN and control
clocks from the PCM Serial Interface. Audio and control data are multiplexed together and bi-phase mark
encoded. The resulting bit stream is driven from the output pin TXOUT to an output connector either directly
or through a transformer. The transmitter is clocked from the clock input pin MCLK.
The channel status (C) bits in the transmitted data stream are taken from storage areas within the CS4265.
The user can manually access the internal storage of the CS4265 to configure the transmitted channel status data. The “Channel Status Buffer Management” section describes the method of manually accessing
the storage areas. The CS4265 transmits all ‘0’s in the user (U) data fields.
4.12.1 TxOut Driver
The line driver is a low skew, low impedance, single-ended output capable of driving cables directly. The
driver is set to ground during reset (RESET = LOW), when no transmit clock is provided, and optionally
DS657F2
29
CS4265
under the control of a register bit. The CS4265 also allows immediate muting of the IEC60958-3 transmitter audio data through a control register bit.
External components are used to terminate and isolate the external cable from the CS4265. These components are detailed in the “External IEC60958-3 Transmitter Components” section on page 51.
4.12.2 Mono Mode Operation
An IEC60958-3 stream may be used in more than one way to transmit 192 kHz sample rate data. One
method is to double the frame rate of the current format. This results is a stereo signal with a sample rate
of 192 kHz. An alternate method is implemented using the two sub-frames in a 96 kHz frame rate
IEC60958-3 signal to carry consecutive samples of a mono signal, resulting in a 192 kHz sample rate
stream. This allows older equipment, whose IEC60958-3 transmitters and receivers are not rated for
192 kHz frame rate operation, to handle 192 kHz sample rate information. In this “mono mode”, two cables are needed for stereo data transfer. The CS4265 offers Mono Mode operation. The CS4265 is placed
into and out of Mono Mode with the MMT control bit.
In Mono Mode, the input port will run at the audio sample rate (Fs), while the IEC60958-3 transmitter
frame rate will be at Fs/2. Consecutive left or right channel serial audio data samples may be selected for
transmission on the A and B sub-frames, and the channel status block transmitted is also selectable.
Using Mono Mode is only necessary if the incoming audio sample rate is already at 192 kHz and contains
both left and right audio data words. The “Mono Mode” IEC60958-3 output stream may also be achieved
by keeping the CS4265 in normal stereo mode and placing consecutive audio samples in the left and right
positions in an incoming 96 kHz word-rate data stream.
4.13
I²C Control Port Description and Timing
The control port is used to access the registers, allowing the CS4265 to be configured for the desired operational modes and formats. The operation of the control port may be completely asynchronous with respect
to the audio sample rates. However, to avoid potential interference problems, the control port pins should
remain static if no operation is required.
SDA is a bidirectional data line. Data is clocked into and out of the part by the clock, SCL. A 47 kΩ pull-up
or pull-down on the SDOUT pin will set AD0, the least significant bit of the chip address. A pull-up to VLS
will set AD0 to ‘1’ and a pull-down to DGND will set AD0 to ‘0’. The state of the SDOUT pin is sensed and
AD0 is set upon the release of RESET.
The signal timings for a read and write cycle are shown in Figure 15 and Figure 16. A Start condition is defined as a falling transition of SDA while the clock is high. A Stop condition is a rising transition while the
clock is high. All other transitions of SDA occur while the clock is low. The first byte sent to the CS4265 after
a Start condition consists of a 7-bit chip address field and an R/W bit (high for a read, low for a write). The
upper 6 bits of the 7-bit address field are fixed at 100111. To communicate with a CS4265, the chip address
field, which is the first byte sent to the CS4265, should match 100111 followed by the setting of AD0. The
eighth bit of the address is the R/W bit. If the operation is a write, the next byte is the Memory Address Pointer (MAP), which selects the register to be read or written. If the operation is a read, the contents of the register pointed to by the MAP will be output. Following each data byte, the memory address pointer will
automatically increment to facilitate block reads and writes of successive registers. Each byte is separated
by an acknowledge bit. The ACK bit is output from the CS4265 after each input byte is read, and is input to
the CS4265 from the microcontroller after each transmitted byte.
30
DS657F2
CS4265
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18
7
6
24 25 26 27 28
19
SCL
CHIP ADDRESS (WRITE)
1
SDA
0
0
1
1
MAP BYTE
1 AD0 0
5
4
3
1
0
7
ACK
6
DATA +n
DATA +1
DATA
2
1
ACK
0
7
6
1
0
7
6
1
0
ACK
ACK
STOP
START
Figure 15. Control Port Timing, I²C Write
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16
17 18
19
20 21 22 23 24 25 26 27 28
SCL
CHIP ADDRESS (WRITE)
SDA
1
0
0
1
1
1
AD0
STOP
MAP BYTE
7
0
6
5
4
3
2
1
CHIP ADDRESS (READ)
1
0
0
0
1
1
1
AD0 1
ACK
ACK
START
DATA
START
7
ACK
DATA +1
0
7
ACK
0
DATA + n
7
0
NO
ACK
STOP
Figure 16. Control Port Timing, I²C Read
Since the read operation cannot set the MAP, an aborted write operation is used as a preamble. As shown
in Figure 16, the write operation is aborted after the acknowledge for the MAP byte by sending a stop condition. The following pseudocode illustrates an aborted write operation followed by a read operation.
Send start condition.
Send 100111x0 (chip address & write operation).
Receive acknowledge bit.
Send MAP byte.
Receive acknowledge bit.
Send stop condition, aborting write.
Send start condition.
Send 100111x1(chip address & read operation).
Receive acknowledge bit.
Receive byte, contents of selected register.
Send acknowledge bit.
Send stop condition.
4.14
Status Reporting
The CS4265 has comprehensive status reporting capabilities. Many conditions can be reported in the status
register, as listed in the status register descriptions. See “Status - Address 0Dh” on page 42. Each source
may be masked off through mask register bits. In addition, each source may be set to rising edge, falling
edge, or level sensitive. Combined with the option of level-sensitive or edge-sensitive modes within the microcontroller, many different configurations are possible, depending on the needs of the equipment designer.
DS657F2
31
CS4265
4.15
Reset
When RESET is low, the CS4265 enters a low-power mode and all internal states are reset, including the
control port and registers, the outputs are muted. When RESET is high, the control port becomes operational, and the desired settings should be loaded into the control registers. Writing a 0 to the PDN bit in the Power Control register will then cause the part to leave the low-power state and begin operation.
The delta-sigma modulators settle in a matter of microseconds after the analog section is powered, either
through the application of power or by setting the RESET pin high. However, the voltage reference will take
much longer to reach a final value due to the presence of external capacitance on the FILT+ pin. During this
voltage reference ramp delay, both SDOUT and DAC outputs will be automatically muted.
It is recommended that RESET be activated if the analog or digital supplies drop below the recommended
operating condition to prevent power-glitch-related issues.
4.16
Synchronization of Multiple Devices
In systems where multiple ADCs are required, care must be taken to achieve simultaneous sampling. To
ensure synchronous sampling, the master clocks and left/right clocks must be the same for all of the
CS4265s in the system. If only one master clock source is needed, one solution is to place one CS4265 in
Master Mode, and slave all of the other CS4265s to the one master. If multiple master clock sources are
needed, a possible solution would be to supply all clocks from the same external source and time the
CS4265 reset with the inactive edge of master clock. This will ensure that all converters begin sampling on
the same clock edge.
4.17
Grounding and Power Supply Decoupling
As with any high-resolution converter, the CS4265 requires careful attention to power supply and grounding
arrangements if its potential performance is to be realized. Figure 9 shows the recommended power arrangements, with VA connected to a clean supply. VD, which powers the digital filter, may be run from the
system logic supply (VLS or VLC) or may be powered from the analog supply (VA) via a resistor. In this
case, no additional devices should be powered from VD. Power supply decoupling capacitors should be as
near to the CS4265 as possible, with the low value ceramic capacitor being the nearest. All signals, especially clocks, should be kept away from the FILT+ and VQ pins in order to avoid unwanted coupling into the
modulators. The FILT+ and VQ decoupling capacitors, particularly the 0.1 µF, must be positioned to minimize the electrical path from FILT+ and AGND. The CS4265 evaluation board demonstrates the optimum
layout and power supply arrangements. To minimize digital noise, connect the CS4265 digital outputs only
to CMOS inputs.
4.18
Package Considerations
The CS4265 is available in the compact QFN package. The under side of the QFN package reveals a large
metal pad that serves as a thermal relief to provide for maximum heat dissipation. This pad must mate with
an equally dimensioned copper pad on the PCB and must be electrically connected to ground. A series of
vias should be used to connect this copper pad to one or more larger ground planes on other PCB layers.
In split ground systems, it is recommended that this thermal pad be connected to AGND for best performance. The CS4265 evaluation board demonstrates the optimum thermal pad and via configuration.
32
DS657F2
CS4265
5. REGISTER QUICK REFERENCE
This table shows the register names and their associated default values.
Addr
Function
01h Chip ID
02h Power Control
7
6
5
4
3
2
1
0
PART3
PART2
PART1
PART0
REV3
REV2
REV1
REV0
1
1
0
1
0
0
0
1
PDN_MIC
PDN_ADC
PDN_DAC
PDN
0
0
0
1
Reserved
MuteDAC
DeEmph
Reserved
Freeze
0
03h DAC Control 1
04h ADC Control
05h MCLK
Frequency
Reserved Reserved Reserved
0
0
Reserved Reserved DAC_DIF1 DAC_DIF0
0
0
FM1
FM0
0
0
0
Reserved
MCLK
Freq2
0
0
06h Signal Selection
SDINSel
07h PGA Ch B
Gain Control
Reserved Reserved
08h PGA Ch A
Gain Control
Reserved Reserved
0
0
0
09h Analog Input
Control
0
0
0
1
0
0
0
Reserved
MuteADC
HPFFreeze
M/S
0
0
0
0
0
MCLK
Freq1
MCLK
Freq0
Reserved
Reserved
Reserved
Reserved
0
0
0
0
0
0
Reserved
Reserved
LOOP
Reserved
Reserved ADC_DIF
Reserved Reserved Reserved
1
0
0
0
0
0
0
0
0
Gain5
Gain4
Gain3
Gain2
Gain1
Gain0
0
0
0
0
0
0
Gain5
Gain4
Gain3
Gain2
Gain1
Gain0
0
0
0
0
0
0
PGASoft
PGAZero
Reserved
Reserved
Select
Reserved Reserved Reserved
0
0
0
1
1
0
0
1
0Ah DAC Ch A Volume Control
Vol7
Vol6
Vol5
Vol4
Vol3
Vol2
Vol1
Vol0
0
0
0
0
0
0
0
0
0Bh DAC Ch B Volume Control
Vol7
Vol6
Vol5
Vol4
Vol3
Vol2
Vol1
Vol0
0
0
0
0Ch DAC Control 2
DACSoft
0Dh Status
Reserved Reserved Reserved
0Eh Status Mask
Reserved Reserved Reserved
0Fh Status Mode
MSB
Reserved Reserved Reserved
0
1
0
0
0
10h Status Mode
LSB
1
0
0
0
0
0
0
0
Reserved Reserved Reserved
0
DS657F2
DACZero InvertDAC Reserved
0
0
0
0
0
0
Reserved
Reserved
Reserved
Reserved
0
0
0
0
0
EFTC
ClkErr
Reserved
ADCOvfl
ADCUndrfl
0
0
0
0
0
EFTCM
ClkErrM
Reserved
ADCOvflM
ADCUndrflM
0
0
0
0
0
EFTC1
ClkErr1
Reserved
ADCOvfl1
ADCUndrfl1
0
0
0
0
0
EFTC0
ClkErr0
Reserved
ADCOvfl0
ADCUndrfl0
0
0
0
0
0
33
CS4265
Addr
Function
11h Transmitter
Control 1
12h Transmitter
Control 2
13h - C-Data Buffer
2Ah
34
7
6
5
4
3
2
1
0
Reserved
EFTCI
CAM
Reserved
Reserved
Reserved
Reserved
Reserved
0
0
0
0
0
0
0
0
Tx_DIF1
Tx_DIF0
TxOff
TxMute
V
MMT
MMTCS
MMTLR
0
0
0
0
0
0
0
0
-
-
-
-
-
-
-
-
DS657F2
CS4265
6. REGISTER DESCRIPTION
6.1
Chip ID - Register 01h
7
PART3
6
PART2
5
PART1
4
PART0
3
REV3
2
REV2
1
REV1
0
REV0
Function:
This register is Read-Only. Bits 7 through 4 are the part number ID, which is 1101b (0Dh), and the remaining
bits (3 through 0) indicate the device revision as shown in Table 4 below.
REV[2:0]
Revision
001
A
010
B, C0
011
C1
Table 4. Device Revision
6.2
Power Control - Address 02h
7
Freeze
6.2.1
6
Reserved
5
Reserved
4
Reserved
3
PDN_MIC
2
PDN_ADC
1
PDN_DAC
0
PDN
Freeze (Bit 7)
Function:
This function allows modifications to be made to certain control port bits without the changes taking effect
until the Freeze bit is disabled. To make multiple changes to these bits take effect simultaneously, set the
Freeze bit, make all changes, then clear the Freeze bit. The bits affected by the Freeze function are listed
in Table 5.
Name
Register
Bit(s)
MuteDAC
03h
2
MuteADC
04h
2
Gain[5:0]
07h
5:0
Gain[5:0]
08h
5:0
Vol[7:0]
0Ah
7:0
Vol[7:0]
0Bh
7:0
TxMute
0Eh
4
Table 5. Freeze-able Bits
6.2.2
Power-Down MIC (Bit 3)
Function:
The microphone preamplifier block will enter a low-power state whenever this bit is set.
6.2.3
Power-Down ADC (Bit 2)
Function:
The ADC pair will remain in a reset state whenever this bit is set.
DS657F2
35
CS4265
6.2.4
Power-Down DAC (Bit 1)
Function:
The DAC pair will remain in a reset state whenever this bit is set.
6.2.5
Power-Down Device (Bit 0)
Function:
The device will enter a low-power state whenever this bit is set. The power-down bit is set by default and
must be cleared before normal operation can occur. The contents of the control registers are retained
when the device is in power-down.
6.3
DAC Control - Address 03h
7
6
5
4
3
2
1
0
Reserved
Reserved
DAC_DIF1
DAC_DIF0
Reserved
MuteDAC
DeEmph
Reserved
6.3.1
DAC Digital Interface Format (Bits 5:4)
Function:
The required relationship between LRCK, SCLK and SDIN for the DAC is defined by the DAC Digital Interface Format and the options are detailed in Table 6 and Figures 5-7.
DAC_DIF1 DAC_DIF0
Description
0
0
Left Justified, up to 24-bit data (default)
0
1
I²S, up to 24-bit data
1
0
Right-Justified, 16-bit Data
1
1
Right-Justified, 24-bit Data
Format
0
1
2
3
Figure
5
6
7
7
Table 6. DAC Digital Interface Formats
6.3.2
Mute DAC (Bit 2)
Function:
The DAC outputs will mute and the MUTEC pin will become active when this bit is set. Though this bit is
active high, it should be noted that the MUTEC pin is active low. The common mode voltage on the outputs
will be retained when this bit is set. The muting function is effected, similar to attenuation changes, by the
DACSoft and DACZero bits in the DAC Control 2 register.
36
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CS4265
6.3.3
De-Emphasis Control (Bit 1)
Function:
The standard 50/15 μs digital de-emphasis filter response, Figure 17, may be implemented for a sample
rate of 44.1 kHz when the DeEmph bit is configured as shown in Table 7. NOTE: De-emphasis is available
only in Single-Speed Mode.
DeEmph
0
1
Description
Disabled (default)
44.1 kHz de-emphasis
Table 7. De-Emphasis Control
Gain
dB
T1=50 µs
0dB
T2 = 15 µs
-10dB
F1
3.183 kHz
F2
Frequency
10.61 kHz
Figure 17. De-Emphasis Curve
6.4
ADC Control - Address 04h
7
6
5
4
3
2
1
0
FM1
FM0
Reserved
ADC_DIF
Reserved
MuteADC
HPFFreeze
M/S
6.4.1
Functional Mode (Bits 7:6)
Function:
Selects the required range of sample rates.
FM1
FM0
Mode
0
0
Single-Speed Mode: 4 to 50 kHz sample rates
0
1
Double-Speed Mode: 50 to 100 kHz sample rates
1
0
Quad-Speed Mode: 100 to 200 kHz sample rates
1
1
Reserved
Table 8. Functional Mode Selection
6.4.2
ADC Digital Interface Format (Bit 4)
Function:
The required relationship between LRCK, SCLK and SDOUT is defined by the ADC Digital Interface Format bit. The options are detailed in Table 9 and may be seen in Figure 5 and Figure 6.
DS657F2
37
CS4265
ADC_DIF
Description
Format
Figure
0
Left-Justified, up to 24-bit data (default)
0
5
1
I²S, up to 24-bit data
1
6
Table 9. ADC Digital Interface Formats
6.4.3
Mute ADC (Bit 2)
Function:
When this bit is set, the serial audio output of the both ADC channels is muted.
6.4.4
ADC High-Pass Filter Freeze (Bit 1)
Function:
When this bit is set, the internal high-pass filter is disabled.The current DC offset value will be frozen and
continue to be subtracted from the conversion result. See “High-Pass Filter and DC Offset Calibration” on
page 25.
6.4.5
Master / Slave Mode (Bit 0)
Function:
This bit selects either master or slave operation for the serial audio port. Setting this bit selects Master
Mode, while clearing this bit selects Slave Mode.
6.5
MCLK Frequency - Address 05h
7
Reserved
6.5.1
6
MCLK
Freq2
5
MCLK
Freq1
4
MCLK
Freq0
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Master Clock Dividers (Bits 6:4)
Function:
Sets the frequency of the supplied MCLK signal. See Table 10 for the appropriate settings.
MCLK Divider
MCLK Freq2
MCLK Freq1
MCLK Freq0
÷1
0
0
0
÷ 1.5
0
0
1
÷2
0
1
0
÷3
0
1
1
÷4
1
0
0
Reserved
1
0
1
Reserved
1
1
x
Table 10. MCLK Frequency
38
DS657F2
CS4265
6.6
Signal Selection - Address 06h
7
6
5
4
3
2
1
0
SDINSel
Reserved
Reserved
Reserved
Reserved
Reserved
LOOP
Reserved
6.6.1
DAC SDIN Source (Bit 7)
Function:
This bit is used to select the serial audio data source for the DAC as shown in Table 11.
SDINSel Setting
DAC Data Source
0
1
SDIN1
SDIN2
Table 11. DAC SDIN Source Selection
6.6.2
Digital Loopback (Bit 1)
Function:
When this bit is set, an internal digital loopback from the ADC to the DAC will be enabled. Please refer to
“Internal Digital Loopback” on page 28.
6.7
Channel B PGA Control - Address 07h
7
Reserved
6.7.1
6
Reserved
5
Gain5
4
Gain4
3
Gain3
2
Gain2
1
Gain1
0
Gain0
3
Gain3
2
Gain2
1
Gain1
0
Gain0
Channel B PGA Gain (Bits 5:0)
Function:
See “Channel A PGA Gain (Bits 5:0)” on page 39.
6.8
Channel A PGA Control - Address 08h
7
Reserved
6.8.1
6
Reserved
5
Gain5
4
Gain4
Channel A PGA Gain (Bits 5:0)
Function:
Sets the gain or attenuation for the ADC input PGA stage. The gain may be adjusted from -12 dB to
+12 dB in 0.5 dB steps. The gain bits are in two’s complement with the Gain0 bit set for a 0.5 dB step.
Register settings outside of the ±12 dB range are reserved and must not be used. See Table 12 for example settings.
Gain[5:0]
Setting
101000
-12 dB
000000
0 dB
011000
+12 dB
Table 12. Example Gain and Attenuation Settings
DS657F2
39
CS4265
6.9
ADC Input Control - Address 09h
7
Reserved
6.9.1
6
Reserved
5
Reserved
4
PGASoft
3
PGAZero
2
Reserved
1
Reserved
0
Select
PGA Soft Ramp or Zero Cross Enable (Bits 4:3)
Function:
Soft Ramp Enable
Soft Ramp allows level changes, both muting and attenuation, to be implemented by incrementally ramping, in 1/8 dB steps, from the current level to the new level at a rate of 1 dB per 8 left/right clock periods.
See Table 13.
Zero Cross Enable
Zero Cross Enable dictates that signal-level changes, either by attenuation changes or muting, will occur
on a signal zero crossing to minimize audible artifacts. The requested level change will occur after a timeout period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sample rate) if the signal
does not encounter a zero crossing. The zero cross function is independently monitored and implemented
for each channel. See Table 13.
Soft Ramp and Zero Cross Enable
Soft Ramp and Zero Cross Enable dictate that signal-level changes, either by attenuation changes or muting, will occur in 1/8 dB steps and be implemented on a signal zero crossing. The 1/8 dB level change will
occur after a time-out period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sample rate) if the signal does not encounter a zero crossing. The zero cross function is independently monitored and implemented for each channel. See Table 13.
PGASoft
0
0
1
1
PGAZeroCross
0
1
0
1
Mode
Changes to affect immediately
Zero Cross enabled
Soft Ramp enabled
Soft Ramp and Zero Cross enabled (default)
Table 13. PGA Soft Cross or Zero Cross Mode Selection
6.9.2
Analog Input Selection (Bit 0)
Function:
These bits are used to select the input source for the PGA and ADC. Please see Table 14.
Select
PGA/ADC Input
0
Microphone-Level Input
1
Line-Level Input
Table 14. Analog Input Selection
6.10
DAC Channel A Volume Control - Address 0Ah
See 6.11 DAC Channel B Volume Control - Address 0Bh.
40
DS657F2
CS4265
6.11
DAC Channel B Volume Control - Address 0Bh
7
Vol7
6.11.1
6
Vol6
5
Vol5
4
Vol4
3
Vol3
2
Vol2
1
Vol1
0
Vol0
Volume Control (Bits 7:0)
Function:
The digital volume control allows the user to attenuate the signal in 0.5 dB increments from 0 to -127 dB.
The Vol0 bit activates a 0.5 dB attenuation when set, and no attenuation when cleared. The Vol[7:1] bits
activate attenuation equal to their decimal equivalent (in dB). Example volume settings are decoded as
shown in Table 15. The volume changes are implemented as dictated by the DACSoft and DACZeroCross bits in the DAC Control 2 register (see Section 6.12.1).
Binary Code
Volume Setting
00000000
0 dB
00000001
-0.5 dB
00101000
-20 dB
00101001
-20.5 dB
11111110
-127 dB
11111111
-127.5 dB
Table 15. Digital Volume Control Example Settings
6.12
DAC Control 2 - Address 0Ch
7
6
5
4
3
2
1
0
DACSoft
DACZero
InvertDAC
Reserved
Reserved
Reserved
Reserved
Reserved
6.12.1 DAC Soft Ramp or Zero Cross Enable (Bits 7:6)
Function:
Soft Ramp Enable
Soft Ramp allows level changes, both muting and attenuation, to be implemented by incrementally ramping, in 1/8 dB steps, from the current level to the new level at a rate of 1 dB per 8 left/right clock periods.
See Table 16.
Zero Cross Enable
Zero Cross Enable dictates that signal-level changes, either by attenuation changes or muting, will occur
on a signal zero crossing to minimize audible artifacts. The requested level change will occur after a timeout period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sample rate) if the signal
does not encounter a zero crossing. The zero cross function is independently monitored and implemented
for each channel. See Table 16.
Soft Ramp and Zero Cross Enable
Soft Ramp and Zero Cross Enable dictate that signal-level changes, either by attenuation changes or muting, will occur in 1/8 dB steps and be implemented on a signal zero crossing. The 1/8 dB level change will
occur after a time-out period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sam-
DS657F2
41
CS4265
ple rate) if the signal does not encounter a zero crossing. The zero cross function is independently monitored and implemented for each channel. See Table 16.
DACSoft
DACZeroCross
Mode
0
0
Changes to affect immediately
0
1
Zero Cross enabled
1
0
Soft Ramp enabled
1
1
Soft Ramp and Zero Cross enabled (default)
Table 16. DAC Soft Cross or Zero Cross Mode Selection
6.12.2 Invert DAC Output (Bit 5)
Function:
When this bit is set, the output of the DAC is inverted.
6.13
Status - Address 0Dh
7
Reserved
6
Reserved
5
Reserved
4
EFTC
3
ClkErr
2
Reserved
1
ADCOvfl
0
ADCUndrfl
For all bits in this register, a ‘1’ means the associated condition has occurred at least once since the register
was last read. A ‘0’ means the associated condition has NOT occurred since the last reading of the register.
Status bits that are masked off in the associated mask register will always be ‘0’ in this register. This register
defaults to 00h.
6.13.1 E to F C-Buffer Transfer
Function:
Indicates the completion of an E to F C-buffer transfer. See “Channel Status Buffer Management” on
page 52 for more information.
6.13.2 Clock Error (Bit 3)
Function:
Indicates the occurrence of a clock error condition.
6.13.3 ADC Overflow (Bit 1)
Function:
Indicates the occurrence of an ADC overflow condition.
6.13.4 ADC Underflow (Bit 0)
Function:
Indicates the occurrence of an ADC underflow condition.
42
DS657F2
CS4265
6.14
Status Mask - Address 0Eh
7
Reserved
6
Reserved
5
Reserved
4
EFTCM
3
ClkErrM
2
Reserved
1
ADCOvflM
0
ADCUndrflM
Function:
The bits of this register serve as a mask for the Status sources found in the register “Status - Address 0Dh”
on page 42. If a mask bit is set to 1, the error is unmasked, meaning that its occurrence will affect the status
register. If a mask bit is set to 0, the error is masked, meaning that its occurrence will not affect the status
register. The bit positions align with the corresponding bits in the Status register.
6.15
Status Mode MSB - Address 0Fh
6.16
Status Mode LSB - Address 10h
7
Reserved
Reserved
6
Reserved
Reserved
5
Reserved
Reserved
4
EFTC1
EFTC0
3
ClkErr1
ClkErr0
2
Reserved
Reserved
1
ADCOvfl1
ADCOvfl0
0
ADCUndrfl1
ADCUndrfl0
Function:
The two Status Mode registers form a 2-bit code for each Status register function. There are three ways to
update the Status register in accordance with the status condition. In the Rising-Edge Active Mode, the status bit becomes active on the arrival of the condition. In the Falling-Edge Active Mode, the status bit becomes active on the removal of the condition. In Level-Active Mode, the status bit is active during the
condition.
00 - Rising edge active
01 - Falling edge active
10 - Level active
11 - Reserved
6.17
Transmitter Control 1 - Address 11h
7
Reserved
6
EFTCI
5
CAM
4
Reserved
3
Reserved
2
Reserved
1
Reserved
0
Reserved
6.17.1 E to F C-Data Buffer Transfer Inhibit (Bit 6)
Function:
When cleared, C-data E to F buffer transfers are allowed. When set, C-data E to F buffer transfers are
inhibited. See “IEC60958-3 Channel Status (C) Bit Management” on page 52.
6.17.2 C-Data Access Mode (Bit 5)
Function:
When cleared, the C-data buffer will operate in One-byte control port access mode. When set, the C-data
buffer will operate in Two-byte control port access mode. See “IEC60958-3 Channel Status (C) Bit Management” on page 52.
DS657F2
43
CS4265
6.18
Transmitter Control 2 - Address 12h
7
Tx_DIF1
6
Tx_DIF0
5
TxOff
4
TxMute
3
V
2
MMT
1
MMTCS
0
MMTLR
6.18.1 Transmitter Digital Interface Format (Bits 7:6)
Function:
The required relationship between LRCK, SCLK and SDIN for the transmitter is defined by the Transmitter
Digital Interface Format and the options are detailed in Table 17 and Figures 5-7.
Tx_DIF1
Tx_DIF0
Description
Format
Figure
0
0
1
1
0
1
0
1
Left Justified, up to 24-bit data (default)
I²S, up to 24-bit data
Right-Justified, 16-bit Data
Right-Justified, 24-bit Data
0
1
2
3
5
6
7
7
Table 17. Transmitter Digital Interface Formats
6.18.2 Transmitter Output Driver Control (Bit 5)
Function:
When this bit is cleared, the transmitter output pin driver will be in the normal operational mode. When
set, the transmitter output pin driver will drive to a constant 0 V.
6.18.3 Transmitter Mute Control (Bit 4)
Function:
When this bit is cleared, the transmitter data will be in the normal operational mode. When set, the transmitter will output all zero data.
6.18.4 Transmitted Validity Bit Control (Bit 3)
Function:
This bit sets the transmitted Validity bit level.
When this bit is cleared, valid linear PCM audio data is indicated. When this bit is set, invalid or non-linear
PCM audio data is indicated.
6.18.5 Transmitter Mono/Stereo Operation Control (Bit 2)
Function:
When this bit is cleared, the transmitter will operate in stereo mode. When set, the transmitter will operate
in Mono Mode with one input channel’s data output in both A and B subframes (see “IEC60958-3 Channel
Status (C) Bit Management” on page 52) and the CS data defined by the MMTCS bit (see Section 6.18.6).
6.18.6 Mono Mode CS Data Source (Bit 1)
Function:
When this bit is cleared, the transmitter will transmit the channel A CS data in the A subframe and the
channel B CS data in the B subframe.
When this bit is set, the transmitter will transmit the CS data defined for the channel selected by the
MMTLR bit in both the A and B subframes.
44
DS657F2
CS4265
6.18.7 Mono Mode Channel Selection (Bit 0)
Function:
When this bit is cleared, channel A input data will be transmitted in both channel A and B subframes in
mono mode. When this bit is set, channel B input data will be transmitted in both channel A and B subframes in Mono Mode.
DS657F2
45
CS4265
7. PARAMETER DEFINITIONS
Dynamic Range
The ratio of the rms value of the signal to the rms sum of all other spectral components over the specified
bandwidth. Dynamic Range is a signal-to-noise ratio measurement over the specified bandwidth made with
a -60 dBFS signal. 60 dB is added to resulting measurement to refer the measurement to full scale. This
technique ensures that the distortion components are below the noise level and do not affect the measurement. This measurement technique has been accepted by the Audio Engineering Society, AES17-1991,
and the Electronic Industries Association of Japan, EIAJ CP-307. Expressed in decibels.
Total Harmonic Distortion + Noise
The ratio of the rms value of the signal to the rms sum of all other spectral components over the specified
bandwidth (typically 10 Hz to 20 kHz), including distortion components. Expressed in decibels. Measured
at -1 and -20 dBFS as suggested in AES17-1991 Annex A.
Frequency Response
A measure of the amplitude response variation from 10 Hz to 20 kHz relative to the amplitude response at
1 kHz. Units in decibels.
Interchannel Isolation
A measure of crosstalk between the left and right channels. Measured for each channel at the converter's
output with no signal to the input under test and a full-scale signal applied to the other channel. Units in decibels.
Interchannel Gain Mismatch
The gain difference between left and right channels. Units in decibels.
Gain Drift
The change in gain value with temperature. Units in ppm/°C.
46
DS657F2
CS4265
8. DAC FILTER PLOTS
Figure 18. DAC Single-Speed Stopband Rejection
Figure 19. DAC Single-Speed Transition Band
0
-1
0.05
-2
0
-3
-0.05
Amplitude dB
Amplitude dB
-4
-5
-6
-0. 1
-0.15
-7
-0. 2
-8
-0.25
-9
-10
0.45
0.46
0.47
0.48
0.49
0.5
0.51
Frequency (normalized to Fs)
0.52
0.53
0.54
0.5 5
0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (normalized to Fs)
0.35
0.4
0.45
Figure 20. DAC Single-Speed Transition Band
Figure 21. DAC Single-Speed Passband Ripple
Figure 22. DAC Double-Speed Stopband Rejection
Figure 23. DAC Double-Speed Transition Band
DS657F2
0.5
47
CS4265
1
0.8
0
0.7
-1
0.6
-2
0.5
Amplitude dB
Amplitude dB
-3
-4
-5
0.4
0.3
0.2
-6
0.1
-7
0
-8
-0. 1
-9
- 10
0.45
0.46
0.47
0.48
0.49
0.5
0.51
Frequency (normalized to Fs)
0.52
0.53
0.54
-0. 2
0.55
0
Figure 24. DAC Double-Speed Transition Band
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (normalized to Fs)
0.35
0.4
0.45
0.5
Figure 25. DAC Double-Speed Passband Ripple
0
0
-10
-10
-20
-20
-30
Amplitude (dB)
Amplitude (dB)
-40
-50
-60
-30
-40
-70
-50
-80
-60
-90
-100
0
0.1
0.2
0.3
0.4
0.5
0.6
Frequency(normalized to Fs)
0.7
0.8
0.9
1
0.35
Figure 26. DAC Quad-Speed Stopband Rejection
0.4
0.45
0.5
0.55
0.6
Frequency(normalized to Fs)
0.65
0.7
0.75
Figure 27. DAC Quad-Speed Transition Band
0
0
-5
-10
-15
Amplitude dB
Amplitude (dB)
-0. 5
-20
-25
-30
-1
-35
-40
-45
-50
0.4
0.45
0.5
0.55
0.6
Frequency(normalized to Fs)
0.65
Figure 28. DAC Quad-Speed Transition Band
48
0.7
-1. 5
0
0.05
0.1
0.15
0.2
0.25
0.3
Frequency (normalized to Fs)
0.35
0.4
0.45
0.5
Figure 29. DAC Quad-Speed Passband Ripple
DS657F2
CS4265
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
Amplitude (dB)
Amplitude (dB)
9. ADC FILTER PLOTS
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
0.40 0.42 0.44
Frequency (norm alized to Fs)
0
0.10
-1
0.08
-2
0.06
-3
0.04
-4
-5
-6
-7
0.58
0.60
0.00
-0.04
-0.06
-0.08
-0.10
0.46 0.47
0.48
0.49
0.5
0.51
0.52
0.53
0.54
0
0.55
Figure 32. ADC Single-Speed Transition Band (Detail)
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
Figure 33. ADC Single-Speed Passband Ripple
Amplitude (dB)
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
0.1
0.05
Frequency (norm alized to Fs)
Frequency (norm alized to Fs)
Amplitude (dB)
0.56
-0.02
-9
0.9
1.0
Frequency (norm alized to Fs)
Figure 34. ADC Double-Speed Stopband Rejection
DS657F2
0.54
0.02
-8
0.0
0.52
Figure 31. ADC Single-Speed Stopband Rejection
Amplitude (dB)
Amplitude (dB)
Figure 30. ADC Single-Speed Stopband Rejection
-10
0.45
0.46 0.48 0.50
Frequency (norm alized to Fs)
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
0.40 0.42 0.44
0.46 0.48 0.50
0.52
0.54
0.56
0.58
0.60
Frequency (norm alized to Fs)
Figure 35. ADC Double-Speed Stopband Rejection
49
0
0.10
-1
0.08
-2
0.06
-3
0.04
Amplitude (dB)
Amplitude (dB)
CS4265
-4
-5
-6
-7
0.02
0.00
-0.02
-0.04
-8
-0.06
-9
-0.08
-10
0.46
0.47
0.48
0.49
0.50
0.51
-0.10
0.00 0.05
0.52
Frequency (norm alized to Fs)
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.15
0.20 0.25 0.30 0.35 0.40 0.45 0.50
Figure 37. ADC Double-Speed Passband Ripple
Amplitude (dB)
Amplitude (dB)
Figure 36. ADC Double-Speed Transition Band (Detail)
0.0
0.10
Frequency (norm alized to Fs)
0.9
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
-100
-110
-120
-130
-140
1.0
0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80 0.85
Frequency (norm alized to Fs)
Frequency (norm alized to Fs)
Figure 38. ADC Quad-Speed Stopband Rejection
Figure 39. ADC Quad-Speed Stopband Rejection
0
0.10
-1
0.08
-3
0.06
-4
0.04
Amplitude (dB)
Amplitude (dB)
-2
-5
-6
-7
-8
-0.04
-0.08
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
Frequency (norm alized to Fs)
Figure 40. ADC Quad-Speed Transition Band (Detail)
50
0.00
-0.02
-0.06
-9
-10
0.10
0.02
-0.10
0.00 0.03 0.05 0.08 0.10 0.13 0.15 0.18 0.20 0.23 0.25 0.28
Frequency (norm alized to Fs)
Figure 41. ADC Quad-Speed Passband Ripple
DS657F2
CS4265
10.EXTERNAL IEC60958-3 TRANSMITTER COMPONENTS
This section details the external components required to interface the IEC60958-3 transmitter to cables and fiberoptic components.
10.1
IEC60958-3 Transmitter External Components
The IEC60958-3 specifications call for an unbalanced drive circuit with an output impedance of 75 Ω ± 20%
and an output drive level of 0.5 volts peak-to-peak ±20% when measured across a 75 Ω load using no cable.
The circuit shown in Figure 42 provides the proper output impedance and drive level using standard 1% resistors. If VD is driven from +3.3 V, use resistor values of 243 Ω in place of the 374 Ω resistor and a 107 Ω
resistor in place of the 90.9 Ω resistor. The standard connector for a consumer application is an RCA phono
socket.
The TXOUT pin may be used to drive TTL or CMOS gates as shown in Figure 43. This circuit may be used
for optical connectors for digital audio as they typically implement TTL or CMOS compatible inputs. This circuit is also useful when driving multiple digital audio outputs as RS422 line drivers typically implement TTL
compatible inputs.
374-R TXP
TXO UT
CS4265
RCA
P hon o
90.9 Ω
Figure 42. Consumer Output Circuit (VD = 5 V)
TXOUT
CS4265
TTL or
CMOS Gate
Figure 43. TTL/CMOS Output Circuit
10.2
Isolating Transformer Requirements
Please refer to Cirrus application note AN134: AES and SPDIF Recommended Transformers for resources
on transformer selection.
DS657F2
51
CS4265
11.CHANNEL STATUS BUFFER MANAGEMENT
The CS4265 has a comprehensive channel status (C) data buffering scheme which allows the user to manage the
C data through the control port.
11.1
IEC60958-3 Channel Status (C) Bit Management
The CS4265 contains sufficient RAM to store a full block of C data for both A and B channels (192x2 = 384
bits). The user may read from, or write to, these RAM buffers through the control port.
The CS4265 manages the flow of channel status data at the block level, meaning that entire blocks of channel status information are buffered at the input, synchronized to the output time base, and then transmitted.
The buffering scheme involves a cascade of two block-sized buffers, named E and F, as shown in Figure 44.
The MSB of each byte represents the first bit in the serial C data stream. For example, the MSB of byte 0
(which is at control port address 13h) is the consumer/professional bit for channel status block A.
The E buffer is accessible from the control port, allowing read and writing of the C data. The F buffer is used
as the source of C data for the IEC60958-3 transmitter. The F buffer accepts block transfers from the E buffer.
A
8-bits
B
8-bits
E
24
w ords
F
To
AE S3
Transm itter
Transm it
D ata
Buffer
C ontrol Port
Figure 44. Channel Status Data Buffer Structure
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DS657F2
CS4265
11.1.1
Accessing the E Buffer
The user can monitor the data being transferred by reading the E buffer, which is mapped into the register
space of the CS4265, through the control port. The user can modify the data to be transmitted by writing
to the E buffer.
The E buffer is only accessible when an MCLK signal is applied to the CS4265 and the device is out of
the power-down state (the PDN bit in register 02h is cleared). If either of these conditions is not met, the
values stored in the E buffer will not change when written via the control port.
The user can configure the status register such that EFTC bit is set whenever an E to F transfer completes. With this configuration in place, periodic polling of the status register allows determination of the
time periods acceptable for E buffer interaction.
Also provided is an “E to F” inhibit bit. The “E to F” buffer transfer is disabled whenever the user sets this
bit. This may be used whenever “long” control port interactions are occurring.
A flowchart for reading and writing to the E buffer is shown in Figure 45. For writing, the sequence starts
after an E to F transfer, which is based on the output timebase.
Begin
Configure the EFTC status bit as
Rising Edge active.
Read the Status Register
(Reg 0Dh)
Is the EFTC bit set?
No
Yes
Optionally set E to F inhibit
Write E data
If set, clear E to F inhibit
Figure 45. Flowchart for Writing the E Buffer
11.2
Serial Copy Management System (SCMS)
The CS4265 allows read/modify/write access to all the channel status bits. For consumer mode SCMS compliance, the host microcontroller needs to manipulate the Category Code, Copy bit and L bit appropriately.
11.3
Channel Status Data E Buffer Access
The E buffer is organized as 24 x 16-bit words. For each word, the most significant byte is the A channel
data, and the least significant byte is the B channel data (see Figure 44).
There are two methods of accessing this memory, known as One-Byte Mode and Two-Byte Mode. The desired mode is selected through a control register bit.
DS657F2
53
CS4265
11.3.1
One-Byte Mode
In many applications, the channel status blocks for the A and B channels will be identical. In this situation,
if the user reads a byte from one of the channel's blocks, the corresponding byte for the other channel will
be the same. Similarly, if the user wrote a byte to one channel's block, it would be necessary to write the
same byte to the other block. One-Byte Mode takes advantage of the often identical nature of A and B
channel status data.
When reading data in One-Byte Mode, a single byte is returned, which can be from channel A or B data,
depending on a register control bit. If a write is being done, the CS4265 expects a single byte to be input
to its control port. This byte will be written to both the A and B locations in the addressed word.
One-Byte Mode saves the user substantial control port access time, as it effectively accesses two byte’s
worth of information in 1 byte's worth of access time. If the control port's auto increment addressing is used
in combination with this mode, multi-byte accesses such as full-block reads or writes can be done especially efficiently.
11.3.2
Two-Byte Mode
There are those applications in which the A and B channel status blocks will not be the same, and the
user is interested in accessing both blocks. In these situations, Two-Byte Mode should be used to access
the E buffer.
In this mode, a read will cause the CS4265 to output two bytes from its control port. The first byte out represents the A channel status data, and the second byte represents the B channel status data. Writing is
similar, in that two bytes must now be input to the CS4265's control port. The A channel status data is
first; B channel status data is second.
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CS4265
12.PACKAGE DIMENSIONS
32L QFN (5 X 5 mm BODY) PACKAGE DRAWING
e
b
D
Pin #1 Corner
Pin #1 Corner
E2
E
A1
L
D2
A
Top View
DIM
A
A1
b
D
D2
E
E2
e
L
INCHES
NOM
--0.0091
0.1969 BSC
0.1299
0.1969 BSC
0.1299
0.0197 BSC
0.0157
MIN
-0.0000
0.0071
0.1280
0.1280
0.0118
Bottom View
Side View
MAX
0.0394
0.0020
0.0110
MIN
-0.00
0.18
0.1319
3.25
0.1319
3.25
0.0197
0.30
MILLIMETERS
NOM
--0.23
5.00 BSC
3.30
5.00 BSC
3.30
0.50 BSC
0.40
NOTE
MAX
1.00
0.05
0.28
3.35
3.35
0.50
1
1
1,2
1
1
1
1
1
1
JEDEC #: MO-220
Controlling Dimension is Millimeters.
Notes:
1. Dimensioning and tolerance per ASME Y 14.5M-1995.
2. Dimensioning lead width applies to the plated terminal and is measured between 0.20 mm and 0.25 mm
from the terminal tip.
13.THERMAL CHARACTERISTICS AND SPECIFICATIONS
Parameters
Package Thermal Resistance
Allowable Junction Temperature
DS657F2
Symbol
2 Layer Board
4 Layer Board
θJA
Min
Typ
Max
Units
-
52
38
-
125
°C/Watt
°C/Watt
°C
55
CS4265
14.ORDERING INFORMATION
Product
CS4265
CS4265
CDB4265
Description
24-bit, 192 kHz
Stereo Audio CODEC
24-bit, 192 kHz
Stereo Audio CODEC
Package Pb-Free
32-QFN
32-QFN
CS4265 Evaluation Board
Yes
Grade
Commercial
Temp Range
-10° to +70° C
Yes
Automotive
-40° to +105° C
No
-
-
Container
Order #
Tube
CS4265-CNZ
Tape & Reel
CS4265-CNZR
Tube
CS4265-DNZ
Tape & Reel
CS4265-DNZR
-
CDB4265
15.REVISION HISTORY
Release
F1
F2
Changes
– Removed the MAP auto-increment functional description from the I²C Control Port Description and Timing
section beginning on page 30.
– Added device revision information to the Chip ID - Register 01h description on page 35.
– Updated the VQ Output Impedance specification in the DC Electrical Characteristics table on page 17.
– Updated the Microphone Interchannel Isolation specification in the ADC Analog Characteristics table on page 15.
– Added Automotive Grade
– Updated the DAC Analog Characteristics table on page 10.
– Updated the ADC Analog Characteristics table on page 13.
– Updated the DC Electrical Characteristics table on page 17.
– Updated the Digital Interface Characteristics table on page 18.
– Updated the Switching Characteristics - Serial Audio Port table on page 19.
– Updated the Typical Connection Diagram on page 23.
– Switched Channel B PGA Control - Address 07h on page 39 and Channel A PGA Control - Address 08h on
page 39.
Contacting Cirrus Logic Support
For all product questions and inquiries, contact a Cirrus Logic Sales Representative.
To find the one nearest you, go to www.cirrus.com
IMPORTANT NOTICE
Cirrus Logic, Inc. and its subsidiaries (“Cirrus”) believe that the information contained in this document is accurate and reliable. However, the information is subject
to change without notice and is provided “AS IS” without warranty of any kind (express or implied). Customers are advised to obtain the latest version of relevant
information to verify, before placing orders, that information being relied on is current and complete. All products are sold subject to the terms and conditions of sale
supplied at the time of order acknowledgment, including those pertaining to warranty, indemnification, and limitation of liability. No responsibility is assumed by Cirrus
for the use of this information, including use of this information as the basis for manufacture or sale of any items, or for infringement of patents or other rights of third
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does not extend to other copying such as copying for general distribution, advertising or promotional purposes, or for creating any work for resale.
CERTAIN APPLICATIONS USING SEMICONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH, PERSONAL INJURY, OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE (“CRITICAL APPLICATIONS”). CIRRUS PRODUCTS ARE NOT DESIGNED, AUTHORIZED OR WARRANTED FOR USE
IN AIRCRAFT SYSTEMS, MILITARY APPLICATIONS, PRODUCTS SURGICALLY IMPLANTED INTO THE BODY, AUTOMOTIVE SAFETY OR SECURITY DEVICES, LIFE SUPPORT PRODUCTS OR OTHER CRITICAL APPLICATIONS. INCLUSION OF CIRRUS PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD
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IN SUCH A MANNER. IF THE CUSTOMER OR CUSTOMER’S CUSTOMER USES OR PERMITS THE USE OF CIRRUS PRODUCTS IN CRITICAL APPLICATIONS, CUSTOMER AGREES, BY SUCH USE, TO FULLY INDEMNIFY CIRRUS, ITS OFFICERS, DIRECTORS, EMPLOYEES, DISTRIBUTORS AND OTHER
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THESE USES.
Cirrus Logic, Cirrus, the Cirrus Logic logo designs, and Popguard are trademarks of Cirrus Logic, Inc. All other brand and product names in this document may be
trademarks or service marks of their respective owners.
I²C is a registered trademark of Philips Semiconductor.
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DS657F2