lm4935rlx National Semiconductor Corporation, lm4935rlx Datasheet - Page 25

• Manufacturer Part Number: lm4935rlx
• Description: Audio Sub-system With Dual-mode Stereo Headphone And Mono High Efficiency Loudspeaker Amplifiers And Multi-purpose Adc
• Manufacturer: National Semiconductor Corporation

12.0 Status & Control Registers
12.4 COMMON CLOCK SETTINGS FOR THE DAC & ADC
The DAC has an over sampling rate of 125 but requires a 250*fs clock at point B. This allows a simple clocking solution as it will
work from 12.000 MHz (common in most systems with Bluetooth or USB) at 48 kHz exactly, the following table describes the clock
required at point B for various clock sample rates in the different DAC modes:
The ADC has an over sampling ratio of 125 so the table below shows the required clock frequency at point C.
Methods for producing these clock frequencies are described in the PLL Section.
DAC Sample Rate (kHz)
ADC Sample Rate (kHz)
11.025
11.025
22.05
22.05
44.1
12
16
24
32
48
12
16
24
8
8
TABLE 4. Common DAC Clock Frequencies
TABLE 5. Common ADC Clock Frequencies
(Continued)
25
Clock Required at B (MHz)
Clock Required at C (MHz)
1.378125
2.75625
2.75625
5.5125
11.025
1.5
12
2
3
4
6
8
1
2
3
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