AK4644 Datasheet, PDF (23/96 Pages) Asahi Kasei Microsystems – Stereo CODEC with MIC/HP/RCV-AMP

ASAHI KASEI
[AK4644]
OPERATION OVERVIEW
„ System Clock
There are the following four clock modes to interface with external devices (see Table 2 and Table 3).
Mode
PMPLL bit
M/S bit
PLL3-0 bits
Figure
PLL Master Mode (Note 36)
1
1
See Table 5
Figure 19
PLL Slave Mode 1
(PLL Reference Clock: MCKI pin)
1
0
See Table 5
Figure 20
PLL Slave Mode 2
(PLL Reference Clock: LRCK or BICK pin)
1
0
See Table 5
Figure 21
Figure 22
EXT Slave Mode
0
0
x
Figure 23
EXT Master Mode
0
1
x
Figure 24
Note 36. If M/S bit = “1”, PMPLL bit = “0” and MCKO bit = “1” during the setting of PLL Master Mode, the invalid
clocks are output from MCKO pin when MCKO bit is “1”.
Table 2. Clock Mode Setting (x: Don’t care)
Mode
PLL Master Mode
PLL Slave Mode
(PLL Reference Clock: MCKI pin)
MCKO bit
0
1
0
1
MCKO pin
“L”
Selected by
PS1-0 bits
“L”
Selected by
PS1-0 bits
MCKI pin
Selected by
PLL3-0 bits
Selected by
PLL3-0 bits
PLL Slave Mode
(PLL Reference Clock: LRCK or BICK pin)
0
“L”
GND
EXT Slave Mode
0
“L”
Selected by
FS1-0 bits
EXT Master Mode
0
“L”
Selected by
FS1-0 bits
Table 3. Clock pins state in Clock Mode
BICK pin
Output
(Selected by
BCKO bit)
Input
(≥ 32fs)
Input
(Selected by
PLL3-0 bits)
Input
(≥ 32fs)
Output
(Selected by
BCKO bit)
LRCK pin
Output
(1fs)
Input
(1fs)
Input
(1fs)
Input
(1fs)
Output
(1fs)
„ Master Mode/Slave Mode
The M/S bit selects either master or slave mode. M/S bit = “1” selects master mode and “0” selects slave mode. When the
AK4644 is power-down mode (PDN pin = “L”) and exits reset state, the AK4644 is slave mode. After exiting reset state,
the AK4644 goes to master mode by changing M/S bit = “1”.
When the AK4644 is used by master mode, LRCK and BICK pins are a floating state until M/S bit becomes “1”. LRCK
and BICK pins of the AK4644 should be pulled-down or pulled-up by the resistor (about 100kΩ) externally to avoid the
floating state.
M/S bit
Mode
0
Slave Mode
1
Master Mode
Table 4. Select Master/Slave Mode
Default
MS0477-E-01
- 23 -
2006/10