AK4586 Datasheet, PDF (32/54 Pages) Asahi Kasei Microsystems – MULTI CHANNEL AUDIO CODEC WITH DIR

ASAHI KASEI
[AK4586]
Digital High Pass Filter
The ADC has a digital high pass filter for DC offset cancel. The cut-off frequency of the HPF is 1.0Hz at fs=48kHz and
also scales with sampling rate (fs).
Overflow Detection
The AK4586 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 = 17.0/fs = 354µs@fs=48kHz). OVF is “L” for 522/fs (=10.9ms
@fs=48kHz) after PDN = “↑”, and then overflow detection is enabled.
Zero detection
The AK4586 has two pins for zero detect flag outputs. Channel grouping can be selected by DZFM2-0 bits (Table 16).
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”. For example, DZF1 is AND of all six channels and DZF2 is disabled (“L”) at
mode 0.
When the input data of all channels in the group 1(group 2) are continuously zeros for 8192 LRCK 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
0
1
2
3
4
5
6
7
DZFM
210
000
001
010
011
100
101
110
111
L1
DZF1
DZF1
DZF1
DZF1
DZF1
DZF1
DZF2
AOUT
R1 L2 R2 L3
DZF1 DZF1 DZF1 DZF1
DZF1 DZF1 DZF1 DZF1
DZF1 DZF1 DZF1 DZF2
DZF1 DZF1 DZF2 DZF2
DZF1 DZF2 DZF2 DZF2
DZF2 DZF2 DZF2 DZF2
DZF2 DZF2 DZF2 DZF2
disable (DZF1=DZF2 = “L”)
R3
DZF1
DZF2
DZF2
DZF2
DZF2
DZF2
DZF2
Default
Table 16. Zero detect control
MS0097-E-01
- 32 -
2001/12