CDB42L56
Evaluation Board for CS42L56
Features
Description
Analog Line and Microphone Level Inputs
– 6 RCA and 3 Stereo 1/8” Jacks
The CDB42L56 is the ideal evaluation platform solution to test
and evaluate the CS42L56.The CS42L56 is a highly integrated, 24-bit, ultra-low power stereo codec based on multi-bit
delta-sigma modulation suitable for low power portable applications. Use of the board requires an analog/digital signal
source, an analyzer and power supplies. A Windows PC-compatible computer is also needed in order to configure the
CS42L56 and the board.
–
Compatible with Single-Ended and Pseudo-Diff.
Input Configurations
Analog Line and Headphone Outputs
– Stereo 1/8” Headphone Jack w/Input Detection
–
4 RCA Jacks for Headphone/Line Outputs
System timing can be provided by the CS8416 (on-board), by
the CS42L56 supplied with a master clock, by the on-board
crystal oscillator or via an I/O stake header with a DSP
connected.
8 to 96 kHz S/PDIF Interface
– CS8416 Digital Audio Receiver
–
CS8406 Digital Audio Transmitter
I/O Stake Header Accessibility
– External Control Port Headers
–
External Direct and Buffered Serial Audio I/O
Headers
Multiple Power Supply options via USB, Battery or
External Power Supplies.
1.8 V to 3.3 V Selectable Logic Interface
USB
µ controller
S/PDIF Tx
(CS8406)
S/PDIF
Din
S/PDIF Rx
(CS8416)
CDB42L56 Evaluation Board
Reset
I2C Interface
PLL
S/PDIF
Dout
The CDB42L56 is programmed via the PC’s USB using Cirrus
Logic’s Microsoft® Windows®-based software (FlexGUI). The
evaluation board may also be configured to accept external
timing and data signals for operation in a user application
during system development.
ORDERING INFORMATION
FlexGUI S/W Control - Windows® Compatible
– Pre-Defined & User-Configurable Scripts
USB/
RS232
RCA phono connectors and stereo 1/8th inch audio jacks are
provided for CS42L56 analog inputs and HP/Line outputs.
Digital I/O connections are provided via RCA phono or optical
connectors to the CS8416 and CS8406 (S/PDIF Rx and Tx).
Oscillator
(socket)
CS42L56
FPGA
Analog Inputs
(Line + MIC)
Analog Outputs
(Line + Headphone)
Reset
Tx SRC
(CS8421)
Rx SRC
(CS8421)
PSIA I/O Header
http://www.cirrus.com
External System
I/O Header
Copyright Cirrus Logic, Inc. 2014
(All Rights Reserved)
FEB '14
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CDB42L56
TABLE OF CONTENTS
1. SYSTEM OVERVIEW ............................................................................................................................. 4
1.1 Control Port and Board Configuration .............................................................................................. 4
1.2 Power ............................................................................................................................................... 4
1.3 Digital Input ....................................................................................................................................... 4
1.3.1 CS8416 S/PDIF Digital Audio Receiver .................................................................................. 4
1.3.1.1 CS8421 Sample Rate Converter (Tx SRC to CS42L56) ............................................. 5
1.4 Digital Output .................................................................................................................................... 5
1.4.1 CS8406 S/PDIF Digital Audio Transmitter .............................................................................. 5
1.4.2 CS8421 Sample Rate Converter (Rx SRC from CS42L56) .................................................... 5
1.5 FPGA ................................................................................................................................................ 5
1.6 Oscillator ........................................................................................................................................... 6
1.7 PLL ................................................................................................................................................... 6
1.8 I/O Stake Headers ............................................................................................................................ 6
1.9 CS42L56 Audio Codec ..................................................................................................................... 6
1.10 Analog Inputs .................................................................................................................................. 6
1.11 Analog Outputs ............................................................................................................................... 7
2. QUICK-START GUIDE ........................................................................................................................... 8
3. CONFIGURATION OPTIONS ................................................................................................................. 9
3.1 S/PDIF In to Analog Out and Analog In to S/PDIF Out .................................................................... 9
3.2 PSIA In to Analog Out and Analog In to PSIA Out ......................................................................... 10
4. SOFTWARE MODE CONTROL ........................................................................................................... 11
4.1 Board Configuration Tab ................................................................................................................ 12
4.2 Codec Configuration Tab ................................................................................................................ 13
4.3 Codec Analog Input Volume Tab .................................................................................................... 14
4.4 Codec DSP Engine Tab ................................................................................................................. 15
4.5 Codec Analog Output Volume Tab ................................................................................................. 16
4.6 Register Maps Tab ......................................................................................................................... 17
5. JUMPER SETTINGS AND SYSTEM CONNECTIONS ........................................................................ 18
6. PERFORMANCE PLOTS ..................................................................................................................... 21
7. CDB42L56 BLOCK DIAGRAM ............................................................................................................ 27
8. CDB42L56 SCHEMATICS ................................................................................................................... 28
9. CDB42L56 LAYOUT ............................................................................................................................ 33
10. REVISION HISTORY .......................................................................................................................... 38
LIST OF FIGURES
Figure 1. Quick-Start Board Layout ............................................................................................................. 8
Figure 2. S/PDIF In to Analog Out and Analog In to S/PDIF Out ................................................................ 9
Figure 3. PSIA In to Analog Out and Analog In to PSIA Out ..................................................................... 10
Figure 4. Board Configuration Tab ............................................................................................................ 12
Figure 5. Codec Configuration Tab ........................................................................................................... 13
Figure 6. Codec Analog Input Volume Tab ............................................................................................... 14
Figure 7. Codec DSP Engine Tab ............................................................................................................. 15
Figure 8. Codec Analog Output Volume Tab ............................................................................................ 16
Figure 9. Register Maps Tab - CS42L56 .................................................................................................. 17
Figure 10. THD+N vs. Freq. - Analog In to Digital Out .............................................................................. 21
Figure 11. THD+N vs. Amplitude - Analog In to Digital Out ...................................................................... 21
Figure 12. FFT - Analog In to Digital Out @ -1 dBFS ............................................................................... 21
Figure 13. FFT - Analog In to Digital Out @ -60 dBFS ............................................................................. 21
Figure 14. FFT - Analog In to Digital Out - No Input ................................................................................. 22
Figure 15. FFT Crosstalk - Analog In to Digital Out
@ -1 dBFS ................................................................................................................................................ 22
Figure 16. Freq. Response - Analog In to Digital Out ............................................................................... 22
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DS851DB1
CDB42L56
Figure 17. Fade-to-Noise Linearity - Analog In to Digital Out ................................................................... 22
Figure 18. THD+N vs. Freq. - Digital In to HP Out .................................................................................... 22
Figure 19. THD+N vs. Amplitude - Digital In to HP Out ............................................................................ 22
Figure 20. THD+N vs. Volume - Digital In to HP Out ................................................................................ 23
Figure 21. FFT - Digital In to HP Out @ 0 dBFS ....................................................................................... 23
Figure 20. FFT - Digital In to HP Out @ -60 dBFS .................................................................................... 23
Figure 21. FFT - Digital In to HP Out - No Input ........................................................................................ 23
Figure 22. FFT - Digital In to HP Out - No Input Wideband ...................................................................... 23
Figure 23. FFT Crosstalk - Digital In to HP Out @ 0 dBFS ....................................................................... 23
Figure 24. Freq. Response - Digital In to HP Out ..................................................................................... 24
Figure 25. Fade-to-Noise Linearity- Digital In to HP Out ........................................................................... 24
Figure 26. THD+N vs. Freq. - Digital In to Line Out .................................................................................. 24
Figure 27. THD+N vs. Amplitude - Digital In to Line Out .......................................................................... 24
Figure 28. THD+N vs. Volume - Digital In to Line Out .............................................................................. 25
Figure 29. FFT Crosstalk - Digital In to Line Out @ 0 dBFS ..................................................................... 25
Figure 28. FFT - Digital In to Line Out @ 0 dBFS ..................................................................................... 25
Figure 29. FFT - Digital In to Line Out @ -60 dBFS .................................................................................. 25
Figure 30. FFT - Digital In to Line Out - No Input ...................................................................................... 25
Figure 31. FFT - Digital In to Line Out - No Input Wideband ..................................................................... 25
Figure 32. Freq. Response - Digital In to Line Out .................................................................................... 26
Figure 33. Fade-to-Noise Linearity- Digital In to Line Out ......................................................................... 26
Figure 34. Block Diagram .......................................................................................................................... 27
Figure 35. CS42L56 & Analog I/O (Schematic Sheet 1) ........................................................................... 28
Figure 36. S/PDIF & Digital Interface (Schematic Sheet 2) ...................................................................... 29
Figure 37. PLL, oscillator and external I/O connections (Schematic Sheet 3) .......................................... 30
Figure 38. Microcontroller and FPGA (Schematic Sheet 4) ...................................................................... 31
Figure 39. Power (Schematic Sheet 5) ..................................................................................................... 32
Figure 40. Silk Screen ............................................................................................................................... 33
Figure 41. Top-Side Layer ........................................................................................................................ 34
Figure 42. GND (Layer 2) .......................................................................................................................... 35
Figure 43. Power (Layer 3) ....................................................................................................................... 36
Figure 44. Bottom Side Layer ................................................................................................................... 37
LIST OF TABLES
Table 1. Analog Input Configuration Jumper and Resistor Settings ........................................................... 7
Table 2. System Connections ................................................................................................................... 18
Table 3. Jumper Settings .......................................................................................................................... 19
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CDB42L56
1. SYSTEM OVERVIEW
The CDB42L56 evaluation platform provides analog and digital interfaces to the CS42L56 and allows for external
DSP and I²C interconnects to the board. On-board peripherals are powered either from the USB connection or from
an external +5 V supply. On-board voltage regulators provide power to the digital and analog cores of the CS42L56.
The CDB42L56 is configured using Cirrus Logic’s Windows-compatible FlexGUI software to read/write to device
registers.
This section describes the various components on the CDB42L56 and how they are used with the CS42L56. Section
2 on page 8 is a simplified quick connect guide provided for user convenience and may be used to quickly configure
the CS42L56. Section 3 on page 9 describes some of the configurations available for transmitting and receiving audio signals. Section 4 on page 11 provides software configuration details. Section 5 on page 18 provides a description of all stake headers and connectors, including the default factory settings of all jumpers. Section 6 on page 21
provides typical performance plots. The CDB42L56 schematic and layout set is shown in Figures 35 through 44.
1.1
Control Port and Board Configuration
The CDB42L56 evaluation board must be programmed using the Windows compatible software (Cirrus Logic FlexGUI) provided. This software allows the user to program the registers of all the programmable components on the board using an I²C interface.
The GUI interfaces with an on-board micro controller through either the USB or the serial port connector.
For a detailed explanation on software controls, refer to Section 4 on page 11.
Alternatively, the I²C interface to the CS42L56 can be directly accessed through an I/O header (J109) to
accept external timing and signals in a user application during system development.
1.2
Power
Power is supplied to the evaluation board through either the +5.0 V test points or the VBUS supply from the
USB. NOTE: The minimum current required for board operation is approximately 300 mA. It may therefore
be necessary to connect the CDB42L56 directly to the USB port on the PC as opposed to a hub or keyboard
port where the current might be limited.
Jumpers connect the CS42L56’s supplies to a low dropout regulated voltage of +1.8 V, +2.5 V or +3.3 V for
VL and +1.8 V or +2.5 V for VLDO, VA and VCP. A selection for a 1.8 V supply from a buck regulator is also
available, providing a more efficient means of evaluating the CS42L56’s performance when powered from
batteries (3 AAA battery connectors are available on the bottom side of the CDB).
For current measurement purposes only, a 1 ohm series resistor is connected to each supply. The current
is easily calculated by measuring the voltage drop across this resistor. NOTE: The stake headers connected
in parallel with these resistors must be shunted with the supplied jumper during normal operation.
WARNING: Please refer to the CS42L56 data sheet for allowable voltage levels.
1.3
1.3.1
Digital Input
CS8416 S/PDIF Digital Audio Receiver
The CS8416 S/PDIF receiver converts an incoming S/PDIF data input stream into PCM data for the
CS42L56 (through the “Transmit” (Tx) Sample Rate Converter (SRC)).
A complete description of the CS8416 (Figure 36 on page 29) and a discussion of the digital audio interface can be found in the CS8416 data sheet.
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DS851DB1
CDB42L56
Configuration of the CS8416 is made using controls in the “Board Configuration” tab of the Cirrus FlexGUI
software. Section 3. “Configuration Options” on page 9 and Section 4. “Software Mode Control” on page 11
provide configuration examples and software details.
1.3.1.1
CS8421 Sample Rate Converter (Tx SRC to CS42L56)
The CS8421 Tx SRC receives PCM digital audio data from either the CS8416 S/PDIF receiver or the AP
PSIA header and synchronizes this data with the CS42L56, regardless of the CS42L56’s master and audio clocks.
A complete description of the CS8421 (Figure 36 on page 29) and a discussion of the digital audio interface can be found in the CS8421 data sheet.
Configuration and routing selections for the CS8421 are made using controls in the “Board Configuration”
tab of the Cirrus FlexGUI software. Section 3. “Configuration Options” on page 9 and Section 4. “Software
Mode Control” on page 11 provide configuration examples and software details.
1.4
1.4.1
Digital Output
CS8406 S/PDIF Digital Audio Transmitter
The CS8406 converts the PCM data generated from the CS42L56 (through the “Receive” (Rx) SRC) to
the standard S/PDIF data stream.
A complete description of the CS8406 (Figure 36 on page 29) and a discussion of the digital audio interface can be found in the CS8406 data sheet.
Configuration of the CS8406 is made using controls in the “Board Configuration” tab of the Cirrus FlexGUI
software. Section 3. “Configuration Options” on page 9 and Section 4. “Software Mode Control” on
page 11 provide configuration examples and software details.
1.4.2
CS8421 Sample Rate Converter (Rx SRC from CS42L56)
The CS8421 Rx SRC receives PCM digital audio data from the CS42L56 and synchronizes this data with
either the CS8406 S/PDIF transmitter or the AP PSIA headers, regardless of the CS42L56’s master and
audio clocks.
A complete description of the CS8421 (Figure 36 on page 29) and a discussion of the digital audio interface can be found in the CS8421 data sheet.
Configuration and routing selections for the CS8421 are made using controls in the “Board Configuration”
tab of the Cirrus FlexGUI software.Section 3. “Configuration Options” on page 9 and Section 4. “Software
Mode Control” on page 11 provide configuration examples and software details.
1.5
FPGA
The FPGA controls the digital signal routing between the CS42L56, CS8406, CS8416, CS8421 (Tx SRC
and Rx SRC), PLL and the I/O stake header. It also provides a divider for the system master clock from an
on-board oscillator to the required devices. Figures 2 and 3 in Section 3 show how the FPGA can route
clocks and data in order to allow the user to test the CS42L56 in various setups.
Configuration and routing selections for the FPGA are made using controls in the “Board Configuration” tab
of the Cirrus FlexGUI software. Section 4 on page 11 provides software configuration details.
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5
CDB42L56
1.6
Oscillator
The socketed on-board oscillator (Y1) can be selected as the system master clock source by using the selections on the “Board Configuration” tab of the Cirrus FlexGUI. Section 4 on page 11 provides software
configuration details.
The oscillator is mounted in pin sockets, allowing easy removal or replacement. The device footprint on the
board will accommodate half-can or full-can sized oscillators.
1.7
PLL
An on-board PLL is used with the FPGA to generate the serial port sub-clocks for the CS42L56’s serial port
when the CS42L56 is set to slave mode. The sub-clocks’ frequencies are selected on the “Board Configuration” tab of the Cirrus FlexGUI. Section 4 on page 11 provides software configuration details.
1.8
I/O Stake Headers
Headers J104 and J109 (Figure 35 on page 28) provide unbuffered bidirectional access to the CS42L56
serial port and control port, respectively. For regular operation, the left two pins on all rows should be shunted to allow the CS42L56 to receive serial and control port data and clocks from the on-board FPGA.
Alternatively, the stake headers provide access to the CS42L56 from external systems simply by removing
all the shunt jumpers from the “USB” and “CDB I/O” positions. The user may then connect a ribbon cable
connector to the “Ext. Sys. Connect” pins for external control of board functions. A single row of “GND” pins
is provided to maintain signal ground integrity. Two unpopulated pull-up resistors are also available should
the user choose to use the CDB42L56 logic supply (VL) externally.
If an external system is used to interface with the CS42L56 through headers J104 and J109, the digital I/O
logic voltage levels must be selected cautiously since the lines between the headers and the device are not
buffered. Please refer to the CS42L56 product data sheet for a detailed explanation on digital I/O interface
specifications. Selections are made using the “Board Configuration” tab of the Cirrus FlexGUI software.
Section 4 on page 11 provides software configuration details.
1.9
CS42L56 Audio Codec
A complete description of the CS42L56 (U3 - Figure 35 on page 28) can be found in the CS42L56 product
data sheet.
The CS42L56 is configured using the Cirrus Logic Windows compatible software FlexGUI. The device configuration registers are directly accessible via the “Register Maps” tab of the Cirrus FlexGUI software. This
tab provides low-level control of each bit. For easier configuration, additional tabs provide high-level control.
Section 4 on page 11 provides software configuration details.
1.10
Analog Inputs
The analog input circuitry on the CDB42L56 has been designed to allow for testing of the CS42L56 in all its
possible analog input configurations. Line or microphone level analog input signals can be provided to the
analog inputs on the CS42L56 through RCA or microphone input jacks (Figure 35 on page 28). Stake header J6 allows the user to select (with jumpers installed) the CS42L56 as the microphone bias source for each
microphone input (CAUTION: Only 2 jumpers may be installed at a time).
Headers J19 and J20 are used to select the desired input for pins AIN3A/AIN1REF and AIN3B/AIN2REF
on the CS42L56. These headers can be used to select between either a single-ended or a pseudo-differential analog input setup. Table 1 provides jumper and resistor settings for the various analog input configurations allowed on the CS42L56. The shaded rows in the table indicate the most commonly used
configurations and do not require any extra resistor modifications.
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DS851DB1
CDB42L56
No.
1.
2.
3.
4.
5.
6.
Analog Input 1
AIN1A AIN1B
S.E.
S.E.
S.E.
P.Diff.
P.Diff.
S.E.
S.E.
S.E.
S.E.
S.E.
Analog Input 2
AIN2A AIN2B
S.E.
S.E.
S.E.
S.E.
S.E.
S.E.
S.E.
P.Diff.
P.Diff.
S.E.
Analog Input 3
AIN3A AIN3B
S.E.
S.E.
S.E.
S.E.
S.E.
S.E.
-
Jumper Settings
J19
J20
1-2
2-3
2-3
2-3
2-3
2-3
1-2
1-2
1-2
1-2
S.E.
P.Diff.
P.Diff.
S.E.
-
-
2-3
1-2
7.
S.E.
P.Diff.
S.E.
P.Diff.
-
-
2-3
1-2
8.
P.Diff.
S.E.
S.E.
P.Diff.
-
-
2-3
1-2
9.
P.Diff.
S.E.
P.Diff.
S.E.
-
-
2-3
1-2
10.
11.
12.
13.
14.
15.
16.
S.E.
P.Diff.
S.E.
P.Diff.
P.Diff.
P.Diff.
P.Diff.
S.E.
P.Diff.
P.Diff.
S.E.
P.Diff.
P.Diff.
P.Diff.
P.Diff.
S.E.
P.Diff.
P.Diff.
S.E.
P.Diff.
P.Diff.
P.Diff.
S.E.
P.Diff.
P.Diff.
P.Diff.
S.E.
P.Diff.
S.E.
-
S.E.
-
1-2
2-3
2-3
2-3
2-3
2-3
2-3
1-2
2-3
1-2
1-2
1-2
1-2
1-2
Resistors Resistors to
to Populate Unpopulate
R86
R41
R109
R51
R86
R51
R86
R109
R41
R109
R41
R51
R86
R41
R109
R51
-
R12
R58
R78
R43
R12
R43
R12
R78
R58
R78
R58
R43
R12
R58
R78
R43
-
Table 1. Analog Input Configuration Jumper and Resistor Settings
Notes:
1. Use headers J7 and J11 to select input signal ground reference (in pseudo-differential mode) as either
the CDB42L56 board ground or the signal ground reference from the external system which the
CDB42L56 receives through the shield of the analog input cable.
2. Resistor modifications are only required if single-ended and pseudo-differential input configurations
need to be used simultaneously on the “A” and “B” inputs of the same analog input channel.
3. Resistor population settings for resistors not shown in the table should be the same as factory defaults.
Figure 35 on page 28 illustrates how the analog inputs are connected and routed. Table 3 on page 19 details the jumper selections.
1.11
Analog Outputs
The CS42L56 analog outputs can be monitored on RCA jacks J15 and J17 for line and J37 and J38 for
headphone outputs. Additionally, the CS42L56 headphone outputs can also be monitored on stereo headphone jack J1 which also allows the user to test the CS42L56’s headphone detect functionality. The
CDB42L56 on-board circuitry drives the headphone detect pin low when a headphone is inserted in J1.
Headers J12 and J4 can be used to select optional 16 or 32 resistive loads for headphone outputs.
Headers J2 and J3 give users the option of receiving filtered or unfiltered outputs on the RCA headphone
output jacks.
Figure 35 on page 28 illustrates how the analog outputs are connected and routed. Table 3 on page 19 provides details on jumper selections for filtered or unfiltered outputs.
DS851DB1
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CDB42L56
2. QUICK-START GUIDE
The following figure is a simplified quick-start guide made for user convenience. The guide configures the board with
a 1.8 V power supply to VLDO, VA and VCP and a 3.3 V power supply to VL. The user may choose from steps 7
through 10 depending on the desired measurement. Refer to Section 3 on page 9 for details on how the various
components on the board interface with each other in different board configuration modes. Refer to Section 4 on
page 11 for descriptions on control settings in the Cirrus FlexGUI software.
.
1
2
Set jumper settings for VL to 3.3 V
and VCP, VLDO and VA to 1.8 V.
3
Set Board Power setting to USB.
J48, J53, J52, J74, J7 and
J11 should be shunted.
6
Connect USB to board.
Open Flex GUI software
on PC and load quick
setup script.
10
Provide Analog
Inputs to board.
*Select which input
channel will be used
through “CODEC
configuration” tab in
software
4
Set desired jumper
settings for J12, J4,
J2, J3.
7
Provide digital inputs to the
board either through the S/
PDIF optical or RCA phono
connectors or through the
PSIA I/O header J78.
8
5
Receive digital outputs from the board either
through the S/PDIF optical or RCA phono
connectors or through the PSIA I/O header
J40.
Left pins on J109 and
J104 should be
shunted.
9
Monitor analog output either via HP or Line Channel
RCA phono connectors or HP stereo jack.
*Select which output channel will be used through
“CODEC configuration” tab in software
Figure 1. Quick-Start Board Layout
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CDB42L56
3. CONFIGURATION OPTIONS
This section shows two common configurations of the CDB42L56.
3.1
S/PDIF In to Analog Out and Analog In to S/PDIF Out
The CS42L56 ADC and DAC performance can be tested by loading the “SPDIF In to Analog Out -- Analog
In to S/PDIF Out” quick setup file provided with the software package. The script configures the digital clock
and data signal routing on the board as shown in Figure 2. The quick setup scripts provided in the software
assume that a 24.000 MHz on-board oscillator is populated in Y1.
A S/PDIF input must be provided as the S/PDIF Tx (CS8406) uses the RMCK signal from the S/PDIF Rx
(CS8416) for synchronization in this configuration, as shown in the Figure 2.
FPGA
Divider
On-Board
Oscillator
Divider
Divider
PLL
MCLK
LINEOUTA
A
B
HP Output
J21
J12
A
B
Tx SRC
(CS8421)
LINEOUTB
Line Output
HPOUTA
16
32
16
32
J4
SCLK
LRCK
SDIN
CS42L56
OSCLK
ISCLK
OLRCK
ILRCK
SDOUT
SDIN
(SLAVE) XTI
S/PDIF Rx
(CS8416)
RX.SCLK
RX.LRCK
RX.SDOUT
RX.RMCK
(MASTER)
S/PDIF
IN
HPOUTB
AIN1A
AIN1A
(SLAVE)
AIN1B
AIN1B
AIN2A
AIN2A
AIN2B
AIN2B
AIN3A
AIN3B
J19
AIN3A
J20
AIN3B
SDOUT
Rx SRC
(CS8421)
ISCLK
OSCLK
ILRCK
OLRCK
SDIN
SDOUT
(SLAVE) XTI
S/PDIF Tx S/PDIF
(CS8406)
OUT
TX.OMCK
TX.SCLK
TX.LRCK
TX.SDIN
(MASTER)
Figure 2. S/PDIF In to Analog Out and Analog In to S/PDIF Out
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CDB42L56
3.2
PSIA In to Analog Out and Analog In to PSIA Out
The CS42L56 ADC and DAC performance can be tested by loading the “PSIA In to Analog Out -- Analog
In to PSIA Out” quick setup file provided with the software package. The script configures the digital clock
and data signal routing on the board as shown in Figure 2. The quick setup scripts provided in the software
assume that a 24.000 MHz on-board oscillator is populated in Y1.
FPGA
Divider
On-Board
Oscillator
Divider
Divider
PLL
MCLK
LINEOUTA
A
B
HP Output
J21
J12
A
B
Tx SRC
(CS8421)
LINEOUTB
Line Output
HPOUTA
16
32
16
32
J4
SCLK
LRCK
SDIN
CS42L56
OSCLK
ISCLK
OLRCK
ILRCK
SDOUT
SDIN
(SLAVE) XTI
PSIA Tx (J78)
TX.SCLK
TX.LRCK
TX.SDOUT
TX.MCLK
(MASTER)
HPOUTB
AIN1A
AIN1A
(SLAVE)
AIN1B
AIN1B
AIN2A
AIN2A
AIN2B
AIN2B
AIN3A
AIN3B
J19
AIN3A
J20
AIN3B
SDOUT
Rx SRC
(CS8421)
ISCLK
OSCLK
ILRCK
OLRCK
SDIN
SDOUT
(SLAVE) XTI
PSIA Rx (J40)
RX.SCLK
RX.LRCK
RX.SDIN
RX.MCLK
(MASTER)
Figure 3. PSIA In to Analog Out and Analog In to PSIA Out
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CDB42L56
4. SOFTWARE MODE CONTROL
The CDB42L56 may be used with the Microsoft® Windows®-based FlexGUI graphical user interface, allowing software control of the CS42L56, FPGA, CS8421, CS8416 and CS8406 registers. The latest control software may be
downloaded from www.cirrus.com/msasoftware. Step-by-step instructions for setting up the FlexGUI are provided
as follows:
1. Download and install the FlexGUI software as instructed on the web site.
2. Connect the CDB to the host PC using a USB cable.
3. Launch the Cirrus FlexGUI. Once the GUI is launched successfully, all registers are set to their default reset
state.
4. Refresh the GUI by clicking on the “Update” button. The default state of all registers are now visible.
For standard set-up:
5. Set up the signal routing in the “Board Configuration” tab as desired.
6. Set up the CS42L56 in the “Codec Configuration”, “Codec Analog Input Volume”, “Codec DSP Engine”, “Codec Analog Output Volume” and “Register Maps” tabs as desired.
7. Begin evaluating the CS42L56.
For quick set-up, the CDB42L56 may, alternatively, be configured by loading a predefined sample script file:
8. On the File menu, click "Restore Board Registers..."
9. Browse to Boards\CDB42L56\Scripts\.
10. Choose any one of the provided scripts to begin evaluation.
To create personal scripts files:
11. On the File menu, click “Save Board Registers...”
12. Enter any name that sufficiently describes the created setup.
13. Choose the desired location and save the script.
14. To load this script, follow the instructions from step 8 above.
DS851DB1
11
CDB42L56
4.1
Board Configuration Tab
The “Board Configuration” tab provides high-level control of signal routing on the CDB42L56. The controls
in this tab are used to setup the CS8416, CS8406, Tx SRC, Rx SRC and the FPGA routing and are divided
into separate control groups for each of these individual devices. A description of each control group is outlined below. This tab also includes a drop down menu with a list of quick-setup configurations. Selecting a
quick-setup from the drop down box, the software loads a predefined configuration for the different devices
on the board. Section 3 on page 9 provides details on some quick-setup configurations.
FPGA Routing - Includes controls to setup the FPGA for using the S/PDIF or the PSIA test interface and for
setting up clock and signal routing for CS42L56 in master/slave mode. This group also has controls for selecting SCLK and LRCK frequencies, perform divide operations on the oscillator.
CS8416 S/PDIF Receiver Control - Controls for the CS8416.
CS8406 S/PDIF Transmitter Control - Controls for the CS8406.
CS8421 SRC Control - Controls for the receive and transmit SRCs. To configure, select the desired SRC
from the drop down menu and then click the update button.
Update - Reads all registers in the FPGA, CS42L56, CS8416, CS8406 and CS8421 and shows the current
values in the GUI.
Reset - Resets FPGA to default routing configuration.
Figure 4. Board Configuration Tab
12
DS851DB1
CDB42L56
4.2
Codec Configuration Tab
The “Codec Configuration” tab provides high-level control of the CS42L56 register settings. Status text detailing the CS42L56’s specific configuration is shown in parenthesis or appears directly below the associated control. This text will change depending on the setting of the associated control. A description of each
control group is outlined below. See the CS42L56 data sheet for complete register descriptions.
Power Control - Controls for powering all devices.
ADC Input Configuration - Controls for input configuration and routing/mixing.
Serial Port Configuration - Controls for all settings related to the serial I/O data and clocks on the board.
Status - Displays status of interrupt bits.
Update - Reads all registers in the CS42L56 and reflects the current values in the GUI.
Reset - Resets the CS42L56.
Figure 5. Codec Configuration Tab
DS851DB1
13
CDB42L56
4.3
Codec Analog Input Volume Tab
The “Codec Analog Input Volume” tab provides high-level control of all volume settings in the ADC of the
CS42L56. Status text detailing the CS42L56’s specific configuration is shown in parenthesis or inside the
control group of the affected control. This text will change depending on the setting of the associated control.
A description of each control group is outlined below.
Digital Volume Control - Digital volume controls and adjustments (ADC output).
ALC Configuration - Configuration settings for the Automatic Level Control (ALC).
Analog Volume Control - Analog volume controls and adjustments for the PGA and MIC amps.
Noise Gate Configuration - Configuration settings for the noise gate.
Update - Reads all registers in the CS42L56 and reflects the current values in the GUI.
Reset - Resets the CS42L56.
Figure 6. Codec Analog Input Volume Tab
14
DS851DB1
CDB42L56
4.4
Codec DSP Engine Tab
The “Codec DSP Engine” tab provides high-level control functions to modify the SDIN (PCM) data volume
level, the ADC output/SDIN mix volume level, the Tone Control and the Beep Generator. Status text detailing the CS42L56’s specific configuration is shown inside the control group of the affected control. This text
will change depending on the setting of the associated control. A description of each control group is outlined below.
Digital Volume Control - Controls for mutes or inverts and the volume/gain of the ADC mix or the PCM mix.
Tone Control - Controls for the corner frequencies and the volume/gain of the treble and bass shelving filters.
Beep Generator - Controls for setting the on/off time, frequency, volume, mix and repeat beep functions.
Update - Reads all registers in the CS42L56 and reflects the current values in the GUI.
Reset - Resets the CS42L56.
Figure 7. Codec DSP Engine Tab
DS851DB1
15
CDB42L56
4.5
Codec Analog Output Volume Tab
The “Codec Analog Output Volume” tab provides high-level control of the CS42L56 class H output amplifier,
HP/Line output volume levels, charge pump frequency, DAC channel limiter, and overall master volume level. A description of each control group is outlined below.
Class H Controls - Controls for defining the digital and analog advisory volume, charge pump frequency,
and adaptive power supply mode for the class H control to determine the appropriate power supply for the
HP/Line amplifiers.
Headphone/Line Amplifiers - Controls for configuring mutes and for setting the volume of the signal from the
headphone/line amplifier and controls for the HP/Line mux.
Limiter - Configuration settings for the peak detect and limiter in the CS42L56.
Master Volume Control - Sets the volume of the signal out of the DSP.
Update - Reads all registers in the CS42L56 and reflects the current values in the GUI.
Reset - Resets the CS42L56.
Figure 8. Codec Analog Output Volume Tab
16
DS851DB1
CDB42L56
4.6
Register Maps Tab
The Register Maps tab provides low-level control of the CS42L56, CS8416, CS8406, CS8421, FPGA and
GPIO register settings. Register values can be modified bit-wise or byte-wise. “Left-clicking” on a particular
register accesses that register and shows its contents at the bottom. The user can change the register contents by using the push-buttons, by selecting a particular bit and typing in the new bit value or by selecting
the register in the map and typing in a new hex value.
Figure 9. Register Maps Tab - CS42L56
17
DS851DB1
CDB42L56
5. JUMPER SETTINGS AND SYSTEM CONNECTIONS
CONNECTOR
REF
INPUT/OUTPUT
SIGNAL PRESENT
EXT. +5V
TP9
Input
+5V power supply for evaluation board
GND
TP10
Input
GND reference from power supply
Ext. Input
TP6
Input
+4.5V external power supply for buck converter
GND
TP7
Input
GND reference from power supply
AAA
BT1
BT2
BT3
Input
Input
Input
Socket for +1.5 V AAA batteries for buck converter
RS232
J95
Input/Output
RS232 serial port connection to PC for I²C control port signals
USB I/O
J94
Input/Output
USB connection to PC for I²C control port signals
S/PDIF Optical IN
OPT3
Input
CS8416 digital audio input via optical cable
S/PDIF Optical OUT
OPT2
Output
CS8406 digital audio output via optical cable
S/PDIF COAX IN
J61
Input
CS8416 digital audio input via coaxial cable
S/PDIF COAX OUT
J68
Output
CS8406 digital audio input via coaxial cable
MICRO RESET
S4
Input
Reset for microcontroller (U84)
CS42L56 RESET
S1
Input
Reset for CS42L56 (U3)
Reload Xilinx program into the FPGA from Flash (U14)
FPGA Program
S2
Input
FPGA JTAG
J75
Input/Output
I/O for programming the FPGA (U5)
MICRO JTAG
J110
Input/Output
I/O for programming the microcontroller (U84)
AP PSIA Transmitter
J78
Input/Output
Digital Data and Clocks to CS42L56
AP PSIA Receiver
J40
Input/Output
Digital Data and Clocks from CS42L56
AIN1B
AIN1A
AIN2B
AIN2A
AIN3B
AIN3A
J14
J10
J21
J18
J23
J24
Input
Input
Input
Input
Input
Input
RCA connectors for analog inputs to CS42L56
AIN1
AIN2
AIN3
J22
J13
J9
Input
Input
Input
Stereo jacks for analog inputs to CS42L56
HP Channel A
HP Channel B
J38
J37
Output
Output
RCA connector for headphone analog output from CS42L56
Line Channel A
Line Channel B
J15
J17
Output
Output
RCA connector for line analog output from CS42L56
HP Stereo Connection
J1
Output
Stereo jack for headphone stereo output from CS42L56
Oscillator for providing master clock for system timing
Oscillator
Y1
Input
I/O Header
J104
Input/Output
I/O for Clocks and Data
S/W CONTROL
J109
Input/Output
I/O for external I²C control port signals
Test Points
TP1-TP2,
TP34-TP36,
TP11-TP16,
TP23, TP25,
TP26, TP28
Outputs
Test Points for monitoring signals to and from CS42L56
Table 2. System Connections
18
DS851DB1
CDB42L56
JMP
J31
J36
LABEL
VL
VCP
PURPOSE
Selects source of voltage for the
VL supply
Selects source of voltage for the
VCP supply
POSITION
*+1.8V
Voltage source is +1.8 V regulator.
+2.5V
Voltage source is +2.5 V regulator.
+3.3V
J25
VA
J28
VLDO
J52
J74
J53
J48
VLDO
VA
VL
VCP
J11
J7
Shunt to RCA
Shunt to RCA
Selects source of voltage for the
VLDO supply
Current Measurement
Voltage source is +1.8 V from battery.
EXT. VL
Voltage source from TP18.
*+1.8V
Voltage source is +1.8 V regulator.
+2.5V
Voltage source is +2.5 V regulator.
+1.8VB
Selects power supply source for
+1.8VB
J19
AIN3A/AIN1REF Input
Selects input source for pin
AIN3A/AIN1REF
J20
AIN3B/AIN2REF Input
Selects input source for pin
AIN3B/AIN2REF
J6
SHUNT TO APPLY
MICBIAS
Selects MICBIAS for analog inputs
J12
HPOUTA
Selects test load from HPOUTA
J4
HPOUTB
Selects test load from HPOUTB
Voltage source from TP17.
Voltage source is +1.8 V regulator.
+2.5V
Voltage source is +2.5 V regulator.
+1.8VB
Voltage source is +1.8 V from battery.
EXT. VA
Voltage source from TP5.
*+1.8V
Voltage source is +1.8 V regulator.
+2.5V
Voltage source is +2.5 V regulator.
+1.8VB
Voltage source is +1.8 V from battery.
EXT. VLDO
Voltage source from TP8.
*SHUNTED
1 series resistor is shorted.
OPEN
1 series resistor in power supply path.
*SHUNTED
AIN2REF and RCAs for AIN2A and AIN2B given
a board ground reference.
OPEN
AIN2REF is given AIN2A and AIN2B ground reference on RCA shield.
*SHUNTED
AIN1REF and RCAs for AIN1A and AIN1B given
a board ground reference.
OPEN
AIN1REF is given AIN1A and AIN1B ground reference on RCA shield.
Provides RCA reference to GND
1.8 V Buck Input
Voltage source is +1.8V from battery.
*+1.8V
Provides RCA reference to GND
J5
Voltage source is +3.3 V regulator.
+1.8VB
EXT. VCP
Selects source of voltage for the
VA supply
FUNCTION SELECTED
1-2
1.8VB is derived from external input TP6.
*2 - 3
1.8VB is derived from AAA batteries.
*1 - 2
AIN3A/AIN1REF is given AIN3A input.
2-3
AIN3A/AIN1REF is given AIN1 ground reference
as input.
*1 - 2
AIN3B/AIN2REF is given AIN3B input.
2-3
AIN3B/AIN2REF is given AIN2 ground reference
as input.
1-3
MICBIAS applied to AIN1A.
2-4
MICBIAS applied to AIN1B.
5-6
MICBIAS applied to AIN2A.
7-8
MICBIAS applied to AIN2B.
9 - 10
MICBIAS applied to AIN3A.
11 - 12
MICBIAS applied to AIN3B.
1-2
32 load selected for HPOUTA.
*2 - 3
16 load selected for HPOUTA.
1-2
32 load selected for HPOUTB.
*2 - 3
16 load selected for HPOUTB.
Table 3. Jumper Settings
19
DS851DB1
CDB42L56
J2
HPOUTA FLT/NOFLT
Selects filtered or unfiltered output
for HPOUTA
*2 - 4, *1 - 3
4 - 6, 3 - 5
RC filtered output selected for HPOUTA.
J3
Selects filtered or unfiltered output
HPOUTB FLT/NOFLT
for HPOUTB
*2 - 4, *1 - 3
Unfiltered output selected for HPOUTB.
4 - 6, 3 - 5
RC filtered output selected for HPOUTB.
J34
J16
Board Power
Tri-state I/O
Selects source of Board Power
Tri-states FGPA I/O
Unfiltered output selected for HPOUTA.
1-2
Board powered from external +5 V source connected to TP9/TP10.
*2 - 3
Board powered from USB.
SHUNTED
*OPEN
FGPA I/O pins are tri-stated.
FGPA I/O pins in normal operation.
*Default factory settings
Table 3. Jumper Settings
20
DS851DB1
CDB42L56
6. PERFORMANCE PLOTS
Test conditions (unless otherwise specified): TA = 25°C; VA=VCP=VLDO=VL=1.8 V; input test signal is a full-scale
997 Hz sine wave; dB values relative to full-scale output; measurement bandwidth 20 Hz to 20 kHz (un-weighted);
Sample Frequency = 48 kHz; +2 dB analog gain for Line Output path; -4 dB analog gain for Headphone Output path;
Headphone test load: RL = 16 ; no LPF option for Headphone Output path.
-60
-60
-62
-62
-64
-64
-66
-66
-68
-68
-70
-70
2.2µF
-72
-72
-74
-74
-76
-76
d
B
F
S
-80
-78
d
B
F
S
10µF
-78
-82
-80
-82
-84
-84
-86
-86
-88
-88
-90
22µF
-90
-92
-92
-94
-94
-96
-96
-98
-98
-100
20
50
100
200
500
1k
2k
5k
10k
-100
-120
20k
-100
-80
Figure 10. THD+N vs. Freq. - Analog In to Digital Out
d
B
F
S
+0
+0
-10
-20
-20
-30
-30
-40
-40
-50
-50
-60
d
B
F
S
-80
-20
-60
-70
-80
-90
-90
-100
-100
-110
-110
-120
-120
-130
-40
Figure 11. THD+N vs. Amplitude - Analog In to Digital Out
-10
-70
-60
dBr
Hz
-130
-140
20
50
100
200
500
1k
2k
5k
10k
20k
-140
20
50
100
200
500
1k
2k
5k
10k
20k
Hz
Hz
Figure 12. FFT - Analog In to Digital Out @ -1 dBFS
Figure 13. FFT - Analog In to Digital Out @ -60 dBFS
Note:
The total harmonic distortion + noise (THD+N) performance of the ADC in the CS42L56 is determined by
the value of the capacitor on the FILT+ pin. Larger capacitor values yield significant improvement in THD+N
at low frequencies. Fig. 10 shows the THD+N vs. frequency performance measured with several FILT+ capacitor values.
DS851DB1
21
CDB42L56
+0
+0
-10
-10
-20
-20
-30
-30
-40
-40
-50
-50
-60
d
B
F
S
-60
d
B
F
S
-70
-80
-70
-80
-90
-90
-100
-100
-110
-110
-120
-120
-130
-130
-140
20
50
100
200
500
1k
2k
5k
10k
-140
20
20k
50
100
200
500
1k
2k
5k
10k
20k
Hz
Hz
Figure 15. FFT Crosstalk - Analog In to Digital Out
Figure 14. FFT - Analog In to Digital Out - No Input
@ -1 dBFS
+5
+40
+4.5
+35
T
+4
+30
+3.5
+25
+3
+2.5
+20
+2
+15
+1.5
+10
+1
d
B
F
S
+0.5
d
B
F
S
+0
-0.5
-1
+5
+0
-5
-10
-1.5
-2
-15
-2.5
-20
-3
-25
-3.5
-30
-4
-35
-4.5
-5
20
TTT
TT T T
50
100
200
500
1k
2k
5k
10k
-40
-140
20k
-120
-100
-80
Hz
Figure 16. Freq. Response - Analog In to Digital Out
-60
-60
-62
-62
-64
-64
-66
-66
-68
-68
-70
-70
-72
-72
-80
-82
A
-84
-78
-80
-82
-84
-86
-86
-88
-88
-90
-90
-92
-92
-94
-94
-96
-96
-98
-98
50
100
200
500
1k
2k
5k
10k
20k
Hz
Figure 18. THD+N vs. Freq. - Digital In to HP Out
22
+0
-76
d
B
r
-78
-100
20
-20
-74
-76
A
-40
Figure 17. Fade-to-Noise Linearity - Analog In to Digital
Out
-74
d
B
r
-60
dBr
-100
-120
-100
-80
-60
-40
-20
+0
dBFS
Figure 19. THD+N vs. Amplitude - Digital In to HP Out
DS851DB1
CDB42L56
-70
+0
-72
-74
-10
-76
-20
-78
-30
-80
-40
-82
-84
Master Volume
(Digital)
-86
d
B
r
-88
-90
-50
-92
A
-94
d
B
r
-60
A
-80
-96
-70
-90
-98
-100
-100
Headphone Volume
(Analog)
-102
-104
-106
-110
-120
-130
-108
-110
-60
-50
-40
-30
-20
-10
-140
20
+0
dBr A
+0
+0
-10
-20
-20
-30
-30
-40
-40
-50
-60
A
-80
d
B
r
-60
A
-80
-90
1k
2k
5k
10k
20k
-70
-100
-110
-110
-120
-120
-130
-130
50
100
200
500
1k
2k
5k
10k
-140
20
20k
Hz
50
100
200
500
1k
2k
5k
10k
20k
Hz
Figure 20. FFT - Digital In to HP Out @ -60 dBFS
Figure 21. FFT - Digital In to HP Out - No Input
+0
+0
-10
-10
-20
-20
-30
-30
-40
-40
-50
-50
d
B
r
-60
-70
d
B
r
A
-80
A
-60
-80
-70
-90
-90
-100
-100
-110
-110
-120
-120
-130
-130
20k
40k
60k
80k
100k
120k
Hz
Figure 22. FFT - Digital In to HP Out - No Input Wideband
DS851DB1
500
-90
-100
-140
200
-50
-70
-140
20
100
Hz
-10
d
B
r
50
Figure 21. FFT - Digital In to HP Out @ 0 dBFS
Figure 20. THD+N vs. Volume - Digital In to HP Out
-140
20
50
100
200
500
1k
2k
5k
10k
20k
Hz
Figure 23. FFT Crosstalk - Digital In to HP Out @ 0 dBFS
23
CDB42L56
+5
+40
+4.5
+35
+4
+30
+3.5
+25
+3
+2.5
+20
+2
+15
+1.5
+10
+1
d
B
r
A
+0
d
B
r
-0.5
A
+0.5
-1
+5
+0
-5
-10
-1.5
-15
-2
-2.5
-20
-3
-25
-3.5
-30
-4
-35
-4.5
-5
20
50
100
200
500
1k
2k
5k
10k
-40
-140
20k
Figure 24. Freq. Response - Digital In to HP Out
-60
-60
-62
-62
-64
-64
-66
-66
-68
-68
-70
-70
-72
-72
-80
-82
A
-84
-40
-20
+0
-78
-80
-82
-84
-86
-86
-88
-88
-90
-90
-92
-92
-94
-94
-96
-96
-98
-98
50
100
200
500
1k
2k
5k
10k
20k
Hz
Figure 26. THD+N vs. Freq. - Digital In to Line Out
24
-60
-76
d
B
r
-78
-100
20
-80
-74
-76
A
-100
Figure 25. Fade-to-Noise Linearity- Digital In to HP Out
-74
d
B
r
-120
dBFS
Hz
-100
-120
-100
-80
-60
-40
-20
+0
dBFS
Figure 27. THD+N vs. Amplitude - Digital In to Line Out
DS851DB1
CDB42L56
-70
+0
-72
-10
-74
-20
-76
-78
-30
-80
-40
-82
-84
-50
-86
d
B
r
A
Master Volume
(Digital)
-88
-90
-92
d
B
r
-60
A
-80
-70
-94
-90
-96
-98
-100
Line Volume
(Analog)
-100
-102
-104
-110
-120
-106
-130
-108
-110
-60
-50
-40
-30
-20
-10
-140
20
+0
50
100
200
500
Figure 28. THD+N vs. Volume - Digital In to Line Out
+0
+0
-10
-20
-20
-30
-30
-40
-40
-60
-70
d
B
r
-80
A
-80
A
-90
-100
-100
-110
-110
-120
-120
-130
-130
50
100
200
500
1k
2k
5k
10k
-140
20
20k
Hz
Figure 28. FFT - Digital In to Line Out @ 0 dBFS
+0
-10
-20
-20
-30
-30
-40
-40
-50
A
-60
-70
-80
A
200
500
1k
2k
5k
10k
20k
-80
-70
-90
-90
-100
-100
-110
-110
-120
-120
-130
-130
50
100
200
500
1k
2k
5k
10k
20k
Hz
Figure 30. FFT - Digital In to Line Out - No Input
DS851DB1
100
-50
d
B
r
-140
20
50
Figure 29. FFT - Digital In to Line Out @ -60 dBFS
+0
-60
20k
Hz
-10
d
B
r
10k
-70
-90
-140
20
5k
-50
-50
-60
2k
Figure 29. FFT Crosstalk - Digital In to Line Out @ 0 dBFS
-10
d
B
r
1k
Hz
dBr A
-140
20k
40k
60k
80k
100k
120k
Hz
Figure 31. FFT - Digital In to Line Out - No Input Wideband
25
CDB42L56
+40
+5
+4.5
+35
+4
+30
+3.5
+25
+3
+20
+2.5
+15
+2
+1.5
+10
+1
d
B
r
A
d
B
r
+0.5
+0
A
-0.5
-1
+5
+0
-5
-10
-1.5
-15
-2
-20
-2.5
-3
-25
-3.5
-30
-4
-35
-4.5
-5
20
50
100
200
500
1k
Hz
2k
5k
10k
20k
Figure 32. Freq. Response - Digital In to Line Out
26
-40
-140
-120
-100
-80
-60
-40
-20
+0
dBFS
Figure 33. Fade-to-Noise Linearity- Digital In to Line Out
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7. CDB42L56 BLOCK DIAGRAM
USB/
RS232
USB
µ controller
Reset
I2C Interface
PLL
S/PDIF
Dout
S/PDIF Tx
(CS8406)
S/PDIF
Din
S/PDIF Rx
(CS8416)
Oscillator
(socket)
CS42L56
FPGA
Analog Inputs
(Line + MIC)
Analog Outputs
(Line + Headphone)
Reset
Tx SRC
(CS8421)
Rx SRC
(CS8421)
PSIA I/O Header
External System
I/O Header
27
CDB42L56
Figure 34. Block Diagram
28
8. CDB42L56 SCHEMATICS
CDB42L56
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Figure 35. CS42L56 & Analog I/O (Schematic Sheet 1)
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29
CDB42L56
Figure 36. S/PDIF & Digital Interface (Schematic Sheet 2)
30
CDB42L56
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Figure 37. PLL, oscillator and external I/O connections (Schematic Sheet 3)
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CDB42L56
31
Figure 38. Microcontroller and FPGA (Schematic Sheet 4)
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CDB42L56
32
Figure 39. Power (Schematic Sheet 5)
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9. CDB42L56 LAYOUT
CDB42L56
33
Figure 40. Silk Screen
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CDB42L56
34
Figure 41. Top-Side Layer
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35
CDB42L56
Figure 42. GND (Layer 2)
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CDB42L56
36
Figure 43. Power (Layer 3)
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37
CDB42L56
Figure 44. Bottom Side Layer
CDB42L56
10.REVISION HISTORY
Revision
DB1
Changes
Initial Release
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
parties. This document is the property of Cirrus and by furnishing this information, Cirrus grants no license, express or implied under any patents, mask work rights,
copyrights, trademarks, trade secrets or other intellectual property rights. Cirrus owns the copyrights associated with the information contained herein and gives
consent for copies to be made of the information only for use within your organization with respect to Cirrus integrated circuits or other products of Cirrus. This consent
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 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 TO BE FULLY AT THE CUSTOMER’S
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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 AGENTS FROM ANY AND ALL
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Cirrus Logic, Cirrus, and the Cirrus Logic logo designs 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.
Microsoft and Windows are registered trademarks of Microsoft Corporation.
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DS851DB1