Cirrus Logic CDB4354 User Manual
Evaluation Board for the CS4354
CDB4354
Features
Requires Only a Digital Signal Source and a
+5 V Power Supply for a Complete Digital-toAnalog Converter System
Demonstrates Recommended Layout and
Grounding Arrangements
CS8416 Receives S/PDIF, & EIAJ-340-
Compatible Digital Audio
Header for External PCM Audio
Single-ended Stereo Analog Outputs
Power and S/PDIF Error Indicator LEDs
Hardware Controls: +5 V/3.3 V select for VL,
De-emphasis select
Current Sense Resistors for CS4354 Supplies
(VA and VL)
Description
The CDB4354 evaluation board is a dedicated platform
designed to facilitate the evaluation of the CS4354 24bit, stereo D/A converter. Evaluation requires an analog
signal analyzer, a digital signal source, and a +5 V power supply. Analog line-level outputs are provided via
RCA phono jacks.
The CS8416 digital audio receiver IC provides the system timing necessary to operate the Digital-to-Analog
converter and will accept S/PDIF and EIAJ-340-compatible audio data. The evaluation board may also be
configured to accept external timing and data signals for
operation in a custom user application during system
development.
To accommodate various system configurations, several hardware controls and resistor population options are
provided. Current sense resistors allow for easy power
calculations during system development.
ORDERING INFORMATION
CDB4354 Evaluation Board
Optical S/PDIF
Input
Coaxial S/PDIF
Input
Direct External
Input
http://www.cirrus.com
Hardware Controls
CS8416
Manual
Reset
CS8416
S/PDIF
Receiver
Clocks &
Serial
Audio
Data
+5V Input, +3.3V Regulator
VL Select:
5V or 3.3V
Clocks &
Data
Selection
(Headers)
Copyright Cirrus Logic, Inc. 2010
(All Rights Reserved)
Power:
Serial
Audio
Clocks &
Data
De-emphasis
CS4354
CS4354
Select
Indicator LEDs
+5V power
+3.3V pow er
VL power
S/P DIF E rror
AOUTA
Filter
Analog
Outputs
AOUTB
Filter
JULY '10
DS895DB1
TABLE OF CONTENTS
1. THE CDB4354 SYSTEM ........................................................................................................................ 3
2. BOARD CONNECTIONS AND SETTINGS ............................................................................................ 5
3. SCHEMATICS AND LAYOUT ........................................................................................................... 7
4. REVISION HISTORY ........................................................................................................................... 11
LIST OF FIGURES
Figure 1. CDB4354 Factory Default Jumper Settings ................................................................................. 6
Figure 2. System Block Diagram and Signal Flow ...................................................................................... 7
Figure 3. CS8416 and CS4354 ................................................................................................................... 8
Figure 4. Power ........................................................................................................................................... 9
Figure 5. Silkscreen Top ........................................................................................................................... 10
Figure 6. Top Side ..................................................................................................................................... 10
Figure 6. Top Side ..................................................................................................................................... 10
Figure 7. Bottom Side ............................................................................................................................... 10
LIST OF TABLES
Table 1. System Connections .................................................................................................................... 5
Table 2. CDB4354 Jumper Pin Block Settings ............................................................................................ 5
Table 3. LED Information ............................................................................................................................ 5
CDB4354
2 DS895DB1
CDB4354
1. THE CDB4354 SYSTEM
The CDB4354 is a dedicated platform for evaluating the CS4354. The CS8416 digital audio interface receiver provides an easy interface to digital audio signal sources, including the majority of digital audio test equipment. The
evaluation board also allows the user to supply external PCM clocks and data directly to the CS4354 through a header block for system development. In addition, hardware controls are available to test board and CS4354-specific features.
The CDB4354 system block diagram and signal flow is shown in Figure 2. The CDB4354 schematics are shown in
Figures 3 and 4.
1.1 CS4354 Digital-to-Analog Converter
The CS4354 is a 24-bit, 2 V
ed) dynamic range. A complete description of the CS4354 is included in the CS4354 datasheet.
ground-centered output digital-to-analog converter with 101 dB (A-weight-
RMS
1.2 CS8416 Digital Audio Receiver
The system receives and decodes the standard S/PDIF data format using a CS8416 Digital Audio Receiver.
The outputs of the CS8416 are standard PCM clocks and data: 256 Fs master clock, serial bit clock, leftright clock, and serial data. The operation of the CS8416 and a discussion of the digital audio interface is
included in the CS8416 datasheet.
The evaluation board has been designed such that the active input can be either optical (OPT1) or coaxial
(J16). However, both inputs cannot be driven simultaneously.
1.3 Input for Serial Audio Clocks and Data
By default, the shunts on header block J6 are placed across columns 1 and 2, marked “SPDIF_RX”, which
routes the serial audio clocks and data from the CS8416 to the CS4354. This makes the S/PDIF inputs on
the evaluation board the default inputs. However, the user may remove these shunts and connect an external source to columns 2 and 3 of header block J6, marked “EXT,” via a ribbon cable. Column 3 of J6 are
GND pins to maintain signal ground integrity when using external clocks and data.
Signals input to header J6 must be at the same voltage level as the VL supply on the evaluation board.
When using the S/PDIF inputs on the evaluation board with columns 1 and 2 of J6 shunted, this requirement
is always met and thus requires no precaution on the user’s part.
Please see the CS4354 datasheet for more information on clocking data into the CS4354.
Note: If the VL supply is set to a low voltage level (VL<1.8 V), termination resistors may need to be added
to the J6 header signals to match the source and transmission-line impedances that are driving the
header. This may be accomplished by soldering resistors across the rows of J6 on the back of the
evaluation board.
1.4 Power Supply Circuitry
Power is supplied to the evaluation board by two binding posts, J2 (+5 V) and GND. The allowable input
voltage range for J2 is 4.75 V to 5.25 V. The VA supply for the CS4354 is sourced directly from the +5 V
supply. The VL supply can be sourced from either the +5 V supply or a +3.3 V regulated version, selected
using J12. Furthermore, the user can have full control over the VL supply voltage by removing the shunt
from J12, and connecting an external supply to pin 2 of J12. When using the S/PDIF inputs, the allowable
voltage range for pin 2 of J12 is 3.13 V to 5.25 V. When using external serial audio clocks and data, the
allowable voltage range for pin 2 of J12 is 1.4 V to 5.25 V.
DS895DB1 3
Power consumption of the CS4354 can be calculated with the measured voltage drop at J4 and J5 when
the shunts are removed.
WARNING: Refer to the CS4354 datasheet for maximum allowable voltages levels. Operation outside of
this range can cause permanent damage to the device.
1.5 Grounding and Power Supply Decoupling
As with any high-performance converter, the CS4354 requires careful attention to power supply and grounding arrangements to optimize performance. Figure 3 details the connections to the CS4354 and Figures 5,
6, and 7 show the component placement and top and bottom layout. The charge-pump and decoupling ca-
pacitors are located as close to the CS4354 as possible.
1.6 Hardware Control
The CDB4354 includes several shuntable jumper pin blocks to test CS4354-specific and board features,
such as:
• De-emphasis and Internal Serial Clock select for the CS4354
• Manual reset for the CS8416
• +5 V/+3.3 V select for the VL supply
Please use Table 2 as a guide to the possible configurations for these controls.
CDB4354
1.7 Analog Output Filtering
The analog output filter circuitry on the CDB4354 has been designed according to the CS4354 datasheet.
This circuit is a first order resistor-capacitor low pass filter with values 470 /2.2 nF, respectively, which sets
the -3 dB pole at 154 kHz. The resulting filter keeps signal attenuation below 0.1 dB at 20 kHz while providing sufficient filtering for noise outside the audio band.
4 DS895DB1
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