SAF7849HL/M295,557 NXP Semiconductors, SAF7849HL/M295,557 Datasheet - Page 42

• Manufacturer Part Number: SAF7849HL/M295,557
• Description: IC AUD DECODER 144LQFP
• Manufacturer: NXP Semiconductors
• Type: Audio Decoderr

Specifications of SAF7849HL/M295,557

• Applications: Audio CD
• Voltage - Supply, Analog: 3 V ~ 3.6 V
• Voltage - Supply, Digital: 1.8V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 144-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 935287932557

NXP Semiconductors
SAF784X_2
Product data sheet
6.5.9.7 Upsample filter (four times)
The de-emphasis filter is controlled via FilterConfig bit DEEMPHCONTROL. The filter can
be enabled or disabled under software control, or automatically by hardware. In the latter
case, the filter is turned on when a ‘pre-emphasis’ bit is detected in the control byte of the
Q-channel subcode, and turned off when this bit is missing.
There are two detection modes possible:
This feature only affects the I
upsampled by a factor of four. The upsampling provides the frequency response
described in
Table 11.
When upsampling is enabled, the audio data output rate on the I
higher than without upsampling. Therefore, the I
higher. This means the I
than normally required for the X-rate when upsampling would be disabled.
Passband
0 Hz to 9 kHz
9 kHz to 20 kHz
-
-
-
-
-
-
-
Fig 22. De-emphasis characteristics
•
•
According to the CD Red Book (IEC 60908) : the ‘pre-emphasis’ bit is only checked
during the lead-in area (allowed to change), and during pauses between tracks
According to the CD Orange Book : pre-emphasis is checked on every subcode frame
Upsample filter frequency response
Table
gain
(dB)
10
0
11.
One chip CD audio device with integrated MP3/WMA decoder
2
Rev. 02 — 9 May 2008
S bclk speed needs to be programmed to be four times higher
2
S, not the EBU output. When it is enabled, the audio data is
Stop-band
-
-
24 kHz
24 kHz to 27 kHz
27 kHz to 35 kHz
35 kHz to 64 kHz
64 kHz to 68 kHz
68 kHz
69 kHz to 88 kHz
(3.18 kHz)
= 50 s
2
S wclk frequency has to be four times
(10.6 kHz)
= 15 s
Attenuation
0.001 dB
0.03 dB
25 dB
38 dB
40 dB
50 dB
31 dB
35 dB
40 dB
2
S interface is four times
frequency
001aag326
SAF784x
© NXP B.V. 2008. All rights reserved.
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