CS4385-CQZR Cirrus Logic Inc, CS4385-CQZR Datasheet - Page 27

• Manufacturer Part Number: CS4385-CQZR
• Description: IC,D/A CONVERTER,OCTAL,24-BIT,QFP,48PIN
• Manufacturer: Cirrus Logic Inc

Specifications of CS4385-CQZR

• Number Of Bits: 24
• Data Interface: Serial
• Number Of Converters: 8
• Voltage Supply Source: Analog and Digital
• Power Dissipation (max): 520mW
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 598-1154 - BOARD EVAL FOR CS4385 DAC
• Settling Time: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

DS671F2
4.6
4.7
De-Emphasis
The CS4385 includes on-chip digital de-emphasis filters. The de-emphasis feature is included to accommo-
date older audio recordings that utilize pre-emphasis equalization as a means of noise reduction.
shows the de-emphasis curve. The frequency response of the de-emphasis curve will scale proportionally
with changes in sample rate, Fs if the input sample rate does not match the coefficient which has been se-
lected.
In Software Mode the required de-emphasis filter coefficients for 32 kHz, 44.1 kHz, or 48 kHz are selected
via the de-emphasis control bits.
In Hardware Mode only the 44.1 kHz coefficient is available (enabled through the M2 pin). If the input sam-
ple rate is not 44.1 kHz and de-emphasis has been selected then the corner frequencies of the de-emphasis
filter will be scaled by a factor of the actual Fs over 44,100.
ATAPI Specification
The CS4385 implements the channel-mixing functions of the ATAPI CD-ROM specification. The
ATAPI functions are applied per A-B pair. Refer to
tion.
SDINx
Right Chan nel
Left Chan nel
Audio D ata
Audio D ata
Figure 21. ATAPI Block Diagram (x = channel pair 1, 2, 3, or 4)
-10dB
Gain
0dB
dB
Figure 20. De-Emphasis Curve
Σ
3.183 kHz
T1=50 µs
F1
Table 9 on page 45
10.61 kHz
A Channel
B Channel
Volume
Volume
Control
Control
F2
T2 = 15 µs
Frequency
and
Σ
Figure 21
for additional informa-
MUTE
MUTE
Aout Ax
AoutBx
CS4385
Figure 20
27