CDB4340 Cirrus Logic Inc, CDB4340 Datasheet - Page 3

• Manufacturer Part Number: CDB4340
• Description: Audio Modules & Development Tools Eval Bd 101dB 96kHz DAC
• Manufacturer: Cirrus Logic Inc

Specifications of CDB4340

• Description/function: Audio D/A
• Operating Supply Voltage: 5 V
• Product: Audio Modules
• For Use With/related Products: CS4340
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

1. CDB4340/41 SYSTEM OVERVIEW
The CDB4340/41 evaluation board is an excellent
means of quickly evaluating the CS4340/41. The
CS8414 digital audio interface receiver provides an
easy interface to digital audio signal sources in-
cluding the majority of digital audio test equip-
ment. The evaluation board also allows the user to
supply clocks and data through a 10-pin header for
system development.
The CDB4340/41 schematic has been partitioned
into 10 schematics shown in Figures 2 through 11.
Each partitioned schematic is represented in the
system diagram shown in Figure 1. Notice that the
the system diagram also includes the interconnec-
tions between the partitioned schematics.
2. CS4340/41 DIGITAL TO ANALOG
A description of the CS4340 is included in the
CS4340 data sheet. A description of the CS4341 is
included in the CS4341 data sheet.
3. CS8414 DIGITAL AUDIO RECEIVER
The system receives and decodes the standard
S/PDIF data format using a CS8414 Digital Audio
Receiver, Figure 4. The outputs of the CS8414 in-
clude a serial bit clock, serial data, left-right clock
(FSYNC), de-emphasis control and a 256 Fs mas-
ter clock. The operation of the CS8414 and a dis-
cussion of the digital audio interface are included in
the CS8414 Datasheet.
During normal operation, the CS8414 operates in
the Channel Status mode where the LED’s display
channel status information for the channel selected
by the CSLR/FCK jumper. This allows the CS8414
to decode the de-emphasis bit from the digital au-
dio interface for control of the CS4340 de-empha-
sis filter.
When the Error Information Switch is activated,
the CS8414 operates in the Error and Frequency in-
DS297DB3
CONVERTER
formation mode. The information displayed by the
LED’s can be decoded by consulting the CS8414
data sheet. It is likely that the de-emphasis control
for the CS4340 will be erroneous and produce an
incorrect audio output if the Error Information
Switch is activated and the CS4340 is in the inter-
nal serial clock mode.
Encoded sample frequency information can be dis-
played provided a proper clock is being applied to
the FCK pin of the CS8414. When an LED is lit,
this indicates a "1" on the corresponding pin locat-
ed on the CS8414. When an LED is off, this indi-
cates a "0" on the corresponding pin. Neither the L
or R option of CSLR/FCK should be selected if the
FCK pin is being driven by a clock signal.
The evaluation board has been designed such that
the input can be either optical or coax (see
Figure 6). However, both inputs cannot be driven
simultaneously.
4. CS8414 DATA FORMAT
The CS8414 data format can be set with jumpers
M0, M1, M2, and M3, as described the CS8414
datasheet. The format selected must be compatible
with the data format of the CS4340 or CS4341,
shown in the CS4340 and CS4341 datasheets.
Please note that the CS8414 does not support all the
possible modes of the CS4340 or CS4341, see Ta-
ble 1 for details. The default settings for M0-M3 on
the evaluation board are given in Tables 3-5.
CS4341
Format
0
1
2
3
4
5
6
7
Table 1. CS8414 Supported Formats
CS4340
Format
0
1
2
3
0
-
-
-
Unsupported
Unsupported
CS8414
Format
2
2
0
5
6
2
External
CDB4340/41
SCLK
Yes
Yes
Yes
Yes
Yes
No
-
-
Internal
SCLK
Yes
Yes
Yes
No
No
No
-
-
3