AK4635 Datasheet, PDF (28/81 Pages) Asahi Kasei Microsystems – 16-Bit Mono CODEC with ALC & MIC/SPK/Video-AMP

[AK4635]
■ PLL Master Mode (PMPLL bit = “1”, M/S bit = “1”)
When an external clock (12MHz, 13.5MHz, 24MHz or 27MHz) is input to the MCKI pin, the MCKO, BICK and FCK
clocks are generated by an internal PLL circuit. The MCKO output frequency is fixed to 256fs, the output is enabled by
MCKO bit. The BICK is selected among 16fs, 32fs or 64fs, by BCKO1-0 bits. (Table 9)
In DSP mode, FCK output can select Duty 50% or High-output only during 1 BICK cycle (Table 10). Except DSP mode,
FCKO bit should be set “0”.
When BICK output frequency is 16fs, the audio interface format supports Mode 0 only (DSP Mode).
AK4635
MCKI
MCKO
BICK
FCK
SDTO
SDTI
12MHz, 13.5MHz,
24MHz, 27MHz
DSP or μP
256fs
16fs, 32fs, 64fs
1fs
MCLK
BCLK
FCK
SDTI
SDTO
Figure 23. PLL Master Mode
Mode
0
1
2
3
BCKO1
BCKO0
BICK Output
Frequency
0
0
16fs
0
1
32fs
1
0
64fs
1
1
N/A
Table 9. BICK Output Frequency at Master Mode
(default)
Mode
FCKO
FCK Output
0
0
Duty = 50%
(default)
1
1
High Width = 1/fBCK
fBCK is BICK Output Frequency.
Table 10. FCK Output at PLL Master Mode and DSP Mode
Rev. 0.6
- 28 -
2007/10