sta335bw STMicroelectronics, sta335bw Datasheet - Page 19

• Manufacturer Part Number: sta335bw
• Description: 2.1 Channels High Efficiency Digital Audio System
• Manufacturer: STMicroelectronics

STA335BW
5.1.2
The external clock frequency provided to the XTI pin must be a multiple of the input sample
frequency (f
The relationship between the input clock and the input sample rate is determined by both
the MCSx and the IR (Input Rate) register bits. The MCSx bits determine the PLL factor
generating the internal clock and the IR bit determines the oversampling ratio used
internally
Table 8.
Interpolation ratio select
The STA335BW has variable interpolation (oversampling) settings such that internal
processing and DDX output rates remain consistent. The first processing block interpolates
by either 2 times or 1 time (pass-through) or provides a 2 times downsample. The
oversampling ratio of this interpolation is determined by the IR bits.
Table 9.
32, 44.1, 48
88.2, 96
176.4, 192
4..3
Bit
Input sample rate
Input sample rate Fs (KHz)
fs (KHz)
R/W
R/W
s
).
Input sampling rates
IR bit settings as a function of input sample rate
176.4
44.1
88.2
192
32
48
96
RST
00
1X
00
01
IR
IR (1..0)
Name
576fs
101
NA
NA
00
00
00
01
01
10
10
IR
Selects internal interpolation ratio based on input I
sample frequency
128fs
64fs
32fs
100
1st stage interpolation ratio
256fs
128fs
64fs
011
MCS(2..0)
2 times downsampling
2 times downsampling
2 times oversampling
2 times oversampling
2 times oversampling
Description
Pass-Through
Pass-Through
384fs
192fs
96fs
010
Register description
512fs
256fs
128fs
001
768fs
384fs
192fs
000
2
S
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