AT85C51SND3B1 Datasheet, PDF (149/263 Pages) ATMEL Corporation – Single-Chip Digital Audio Decoder - Encoder with USB 2.0 Interface

Audio Controller
Clock Generator
Audio Processor
AT85C51SND3Bx
The Audio Controller embedded in AT85C51SND3Bx is based on four functional blocks
detailed in the following sections:
• The Clock Generator
• The Audio Processor
• The Audio Codec
• The Audio DAC Interface
Figure 69. Audio Controller Block Diagram
CPU
Bus
DFC
Bus
Audio Processor
AUD
CLOCK
Clock
Generator
Audio DAC
Interface
Audio Codec
OCLK
DCLK
DDAT
DSEL
MICBIAS
MICIN
LINR
LINL
OUTR
OUTL
The clock generator generates the audio controller clocks based on the audio clock
issued by the clock controller as detailed in Section “System Clock Generator”, page 29.
As shown in Figure 70, it contains an Audio Frequencies Generator able to generate the
audio sampling and over-sampling frequencies fed by a normalized clock. This genera-
tor is based on a PLL and is entirely controlled by the audio processor depending on the
encoded or decoded audio stream characteristics.
Figure 70. Audio Controller Clock Generator
AUD
CLOCK
ACCKEN
AUCON.0
Clock
Normalizing
Audio Frequencies
Generator
The audio processor is based on three functional blocks as shown in Figure 71.
• The Audio Buffer
• The Digital Audio Processor
• The Baseband Processor
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