CDB4328 International Power Sources, Inc., CDB4328 Datasheet - Page 7

• Manufacturer Part Number: CDB4328
• Description: 18-bit, Stereo D/A Converter For Digital Audio
• Manufacturer: International Power Sources, Inc.

latch data. Table 2 lists the four formats, along
with the associated figure number. Format 0 is
compatible with existing 16-bit D/A converters
and digital filters. Format 1 is an 18-bit version
of format 0. Format 2 is similar to Crystal ADCs
and many DSP serial ports. Format 3 is compat-
ible with the I
and 3 support 18-bit input or 16-bit followed by
two zeros. In all four serial input modes, the se-
rial data is MSB-first and 2’s-complement
format.
Formats 0, 2 and 3 will operate with 16-bit data
and 16 BICK pulses as well. See Figure 6 for
1 6-bit
BICK = 64 IWR is recommended to minimize
the possibility of performance degradation result-
ing from BICK coupling into VREF-.
DS62F3
DIF1
0
0
1
1
timing.
Table 2. Digital Input Formats
DIF0
2
S serial data protocol. Formats 2
0
1
0
1
"Kickstart"
XTI/XTO
LRCK
ACK0
RST
However,
Mode
0
1
2
3
the
Figure 2. RESET Cancellation Timing
minimum
40 ns
Figure
use
Reset Status
3
3
4
5
of
minimum
40 ns
Reset and Offset Calibration
RST is an active low signal that resets the digital
filter and the delta-sigma modulator, synchro-
nizes LRCK with internal control signals and
starts an offset calibration cycle upon exiting re-
set. When RST goes low, CALO goes high and
stays high until the end of an offset calibration
cycle. An offset calibration cycle takes 1024
IWR cycles to complete. CALO must be con-
nected to CALI and CMPO must be connected
to CMPI for offset calibration. During an offset
calibration the analog output is forced to zero.
Power-Up Considerations
Upon initial application of power to the DAC,
offset calibration and digital filter registers will
be indeterminate. RST should be low during
power-up to activate an internal mute and pre-
vent this erroneous information from being
output from the DAC. Bringing RST high will
begin a calibration cycle and initialize these reg-
isters.
Muting
There are two types of mutes that can be imple-
mented with the CS4328. The first is a -50 dB
Exit Reset
CS4328
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