AK4589_1 Datasheet, PDF (33/76 Pages) Asahi Kasei Microsystems – 2/8-Channel Audio CODEC with DIR

ASAHI KASEI
[AK4589]
Overflow Detection
The AK4589 has overflow detect function for analog input. Overflow detect function is enable if OVFE bit is set to “1”.
OVF pin goes to “H” if analog input of Lch or Rch overflows (more than -0.3dBFS). OVF output for overflowed analog
input has the same group delay as ADC (GD = 16/fs = 333µs @fs=48kHz). OVF pin is “L” for 522/fs (=11.8ms
@fs=48kHz) after PDN = “↑”, and then overflow detection is enabled.
Zero Detection
The AK4589 has two pins for zero detect flag outputs. Channel grouping can be selected by DZFM3-0 bits (Table 13).
DZF1 pin corresponds to the group 1 channels and DZF2 pin corresponds to the group 2 channels. However DZF2 pin
becomes OVF pin if OVFE bit is set to “1”. Zero detection mode is set to mode 0. DZF1 is AND of all eight channels
and DZF2 is disabled (“L”) at mode 0. Table 14 shows the relation of OVFE bit and DZF.
When the input data of all channels in the group 1(group 2) are continuously zeros for 8192 LRCK1 cycles, DZF1
(DZF2) pin goes to “H”. DZF1 (DZF2) pin immediately goes to “L” if input data of any channels in the group 1 (group
2) is not zero after going DZF1 (DZF2) “H”.
Mode
3
DZFM
21
0
0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000
9 1001
10 1 0 1 0
11 1 0 1 1
12 1 1 0 0
13 1 1 0 1
14 1 1 1 0
15 1 1 1 1
L1
DZF1
DZF1
DZF1
DZF1
DZF1
DZF1
DZF2
DZF1
DZF1
R1
DZF1
DZF1
DZF1
DZF1
DZF1
DZF2
DZF2
DZF1
DZF1
AOUT
L2
R2
L3
R3
DZF1 DZF1 DZF1 DZF1
DZF1 DZF1 DZF1 DZF2
DZF1 DZF1 DZF2 DZF2
DZF1 DZF2 DZF2 DZF2
DZF2 DZF2 DZF2 DZF2
DZF2 DZF2 DZF2 DZF2
DZF2 DZF2 DZF2 DZF2
Disable (DZF1=DZF2 = “L”)
DZF1 DZF1 DZF1 DZF1
DZF1 DZF1 DZF1 DZF1
Disable (DZF1=DZF2 = “L”)
Table 13. Zero detect control
L4
DZF1
DZF2
DZF2
DZF2
DZF2
DZF2
DZF2
DZF1
DZF2
R4
DZF1
DZF2
DZF2
DZF2
DZF2
DZF2
DZF2
DZF2
DZF2
Default
OVFE bit
0
1
DZF1 pin
DZF2/OVF pin
Selectable (Table 13) Selectable (Table 13)
Selectable (Table 13)
OVF output
Table 14. DZF1-2 pins outputs
MS0339-E-00
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2004/09