CDB4382 Cirrus Logic Inc, CDB4382 Datasheet - Page 4

• Manufacturer Part Number: CDB4382
• Description: Development Kit
• Manufacturer: Cirrus Logic Inc

Specifications of CDB4382

• Silicon Manufacturer: Cirrus Logic
• Application Sub Type: DAC
• Kit Application Type: Data Converter
• Silicon Core Number: CS4382
• Kit Contents: Evaluation Board
• Rohs Compliant: No
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

in either SPI or I
the CS4382 registers are write-only.
7. DSD OPERATION
The CDB4382 supports Direct Stream Digital
(DSD) operation through the header for external
clocks and data, J16. The CS4382 must be placed
into the DSD mode and headers J6 and J14 must be
set accordingly. See Table 2 for more information.
8. ANALOG OUTPUT FILTER
The analog output filter on the CDB4382 has been
designed to add flexibility when evaluating the
CS4382. The output filter was designed in an op-
tional two stage format, with the first optional stage
being an instrumentation amplifier design and the
second is a 2-pole butterworth filter.
The 2-pole filter is designed to have the in-band
impedance matched between the positive and neg-
ative legs. It also provides a balanced to single end-
ed conversion for standard un-balanced outputs.
The instrumentation amplifier is optionally insert-
ed by changing the FILT jumpers to position 2 (se-
lectable per channel by J37 & 38, J39 & 40, etc.).
This instrumentation amplifier incorporates a 5x
gain (+14dB) which effectively lowers the noise
contribution of the 2-pole filter which improves the
4
SPDIF INPUT - OPTO-1
SPDIF INPUT - J2
PCM INPUT - J15
OUTA1 to OUTB4
DSD INPUT - J16
CONNECTOR
EXT CTRL I/O
PC Port
+18V
GND
-18V
VLS
VLC
+5V
VD
2
C mode; however, in SPI mode
INPUT/OUTPUT
Input/Output
Input/Output
Output
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Input
Table 1. System Connections
+ 5 Volt power
+ 2.5 to +5V power for the CS4382 digital supply
+ 1.8 to +5V power for the CS4382 serial interface
+ 1.8 to +5V power for the CS4382 control interface
-18 to -5V negative supply for the op-amps
+5 to +18V positive supply for the op-amps
Ground connection from power supply
Digital audio interface input via coax
Digital audio interface input via optical
Input for master, serial, left/right clocks and serial data
Input for DSD data and clock
Parallel connection to PC for SPI / I
I/O for SPI / I
Channels 1A to 4B line level analog outputs
overall dynamic range of the system. The gain of
this stage is determined from the following equa-
tion:
The resistor designated by R
adjusted to change the gain of the Instrumentation
amp, and the feedback resistors on the two sides of
the instrumentation amp ‘R’ must be equal.
A resistor divider has been placed before the RCA
jack which brings the signal level back to 2 Vrms
(selectable per channel with jumpers J21 to J28).
Note: This resistor divider may introduce more dis-
tortion from the second filter stage’s op-amp..
2
Figure 1. Instrumentation Amplifier Configuration
C control port signals
SIGNAL PRESENT
Gain
2
=
C control port signals
1
+
2
(see Figure 1) can be
2 R
-----------
R 2
CDB4382