WM8731 Wolfson Microelectronics Ltd., WM8731 Datasheet - Page 40

• Manufacturer Part Number: WM8731
• Description: WM8731 : Low Power Audio Codec With Integrated Headphone Driver
• Manufacturer: Wolfson Microelectronics Ltd.

WM8731
The exact sample rates achieved are defined by the relationships in Table 18 below.
128/192fs NORMAL MODE
The Normal Mode sample rates are designed for standard 256fs and 384fs MCLK rates. However the
WM8731 is also capable of being clocked from a 128 or 192fs MCLK for application over limited
sampling rates as shown in the table below.
Table 19 128fs Normal Mode Sample Rate Look-up Table
512/768fs NORMAL MODE
512 fs and 768 fs MCLK rates can be accommodated by using the CLKIDIV2 bit (Register 8, bit 6).
The core clock to the DSP will be divided by 2 so an external 512/768 fs MCLK will become 256/384
fs internally and the device otherwise operates as in Table 15 but with MCLK at twice the specified
rate. See Table 12 for software control.
Table 18 Normal Mode Actual Sample Rates
SAMPLING
ADC
44.1
kHz
TARGET
48
SAMPLING
RATE
44.1
88.2
kHz
32
48
96
RATE
8
DAC
44.1
kHz
48
12.288MHz/256 x 1/6
12.288MHz/256 x 2/3
MCLK=12.288
12.288MHz/256 x 2
not available
not available
12.288MHz/256
FREQUENCY
kHz
5.6448
8.4672
32
48
96
MCLK
6.144
9.216
8
MHz
BOSR=0
(256fs)
BOSR
11.2896MHz/256 x 2/11
MCLK=11.2896
11.2896MHz/256 x 2
0
1
0
1
not available
11.2896MHz/256
not available
not available
8.018
44.1
88.2
ACTUAL SAMPLING RATE
kHz
SR3
REGISTER SETTINGS
0
0
1
1
SAMPLE
RATE
SR2
1
1
1
1
18.432MHz/384 x 1/6
18.432MHz/384x 2/3
18.432MHz/384 x 2
MCLK=18.432
not available
not available
18.432MHz/384
SR1
kHz
32
48
96
8
1
1
1
1
AI Rev 2.3 August 2001
Advanced Information
BOSR=1
SR0
(384fs)
1
1
1
1
16.9344MHz/384 x 2/11
16.9344MHz /384 x 2
MCLK=16.9344
16.9344MHz /384
not available
not available
not available
DIGITAL
FILTER
TYPE
8.018
44.1
88.2
kHz
2
2
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