WM8524 Production Data
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PD, Rev 4.1, October 2011
14
Figure 8 I
2
S Justified Audio Interface (assuming n-bit word length)
DIGITAL AUDIO DATA SAMPLING RATES
The external master clock is applied directly to the MCLK input pin. In a system where there are a
number of possible sources for the reference clock, it is recommended that the clock source with the
lowest jitter be used for the master clock to optimise the performance of the WM8524.
The WM8524 has a detection circuit that automatically determines the relationship between the
master clock frequency (MCLK) and the sampling rate (LRCLK), to within ±32 system clock periods.
The MCLK must be synchronised with the LRCLK, although the device is tolerant of phase variations
or jitter on the MCLK.
If during sample rate change the ratio between MCLK and LRCLK varies more than once within 1026
LRCLK periods, then it is recommended that the device be taken into the standby state or the off
state before the sample rate change and held in standby until the sample rate change is complete.
This will ensure correct operation of the detection circuit on the return to the enabled state. For details
on the standby state, please refer to the Power up and down control section of the datasheet on page
16.
The DAC supports MCLK to LRCLK ratios of 128fs to 1152fs and sampling rates of 8kHz to 192kHz.
Table 3 shows typical master clock frequencies and sampling rates supported by the WM8524 DAC.
Sampling Rate
LRCLK
MASTER CLOCK FREQUENCY (MHz)
128fs 192fs 256fs 384fs 512fs 768fs 1152fs
8kHz Unavailable Unavailable 2.048 3.072 4.096 6.144 9.216
32kHz Unavailable Unavailable 8.192 12.288 16.384 24.576 36.864
44.1kHz Unavailable Unavailable 11.2896 16.9344 22.5792 33.8688 Unavailable
48kHz Unavailable Unavailable 12.288 18.432 24.576 36.864 Unavailable
88.2kHz 11.2896 16.9344 22.5792 33.8688 Unavailable Unavailable Unavailable
96kHz 12.288 18.432 24.576 36.864 Unavailable Unavailable Unavailable
176.4kHz 22.5792 33.8688 Unavailable Unavailable Unavailable Unavailable Unavailable
192kHz 24.576 36.864 Unavailable Unavailable Unavailable Unavailable Unavailable
Table 3 MCLK Frequencies and Audio Sample Rates
