AK4951AEN Datasheet, PDF (94/105 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/HP/SPK-AMP

[AK4951A]
■ Microphone Input Recording (Stereo)
FS3-0 bits ₁₀₁₁
(Addr:06H, D3-0)
(1)
MGAIN3-0 bits
PMMP bit
0,110,0
(Addr:02H, D6,D2-0, D3)
(2)
Signal Select
(Addr:03H, D3-0)
Timer Select
(Addr:09H)
ALC Setting
(Addr:0AH, 0BH )
REF7-0 bits
(Addr:0CH)
IVL7-0 bits
(Addr:0DH)
0000
(3)
00H
(4)
60H,00H
(5)
E1H
(6)
E1H
(7)
Auto HPF Setting
(Addr:1AH)
Filter Select
(Addr:1BH,1CH,30H)
0CH
(8)
01H,00H,00H
(9)
Digital Filter Path
(Addr:1DH)
03H
(10)
Filter Co-efficient
(Addr:1EH-2FH, 32H-4FH)
ALC State
xxH
(11)
ALC Disable
1011
0,110, 1
0000
00H
6CH,2EH
E1H
E1H
2CH
01H, xxH,xxH
03H
xxH
ALC Enable
6CH,0EH
(14)
ALC Disable
Example:
PLL Master Mode
Audio I/F Format: I2S Compatible
MIC Amp: +18dB
MIC Power 1 ON
Sampling Frequency: 48kHz
ALC setting: Refer to Table 42
HPF1: fc=3.7Hz, ADRST1-0 bits = “00”
Auto HPF ON
(1) Addr:06H, Data:0BH
(2) Addr:02H, Data:0EH
(3) Addr:03H, Data:00H
(4) Addr:09H, Data:00H
(5) Addr:0AH, Data:6CH
Addr:0BH, Data:2EH
(6) Addr:0CH, Data:E1H
(7) Addr:0DH, Data:E1H
(8) Addr:1AH, Data:2CH
(9) Addr:1BH, Data:01H
Addr:1CH, Data:xxH
Addr:30H, Data:xxH
(10) Addr:1DH, Data:03H
(11) Addr:1EH-2FH, Data:xxH
Addr:32H-4FH, Data:xxH
PMPFIL bit
PMADL/R bit
(Addr:00H, D7, D1-0)
SDTO pin
State
(12) Addr:00H, Data:C3H
(12) _1059/fs
(13)
0 data Output
Initialize
Normal
Data Output
0 data output
Figure 63. Microphone Input Recording Sequence
Recording
(13) Addr:00H, Data:40H
(14) Addr:0BH, Data:0EH
<Sequence>
This sequence is an example of ALC setting at fs= 48kHz. For changing the parameter of ALC, please
refer to Table 43. At first, clocks should be supplied according to “Clock Set Up” sequence.
(1) Set up a sampling frequency (FS3-0 bits). When the AK4951A is in PLL mode, Microphone, ADC
and Programmable Filter of (12) must be powered-up in consideration of PLL lock time after a
sampling frequency is changed.
(2) Set up Microphone Amp and Microphone Power. (Addr = 02H)
(3) Set up Input Signal. (Addr = 03H)
(4) Set up FRN, FRATT and ADRST1-0 bits (Addr = 09H)
(5) Set up ALC mode. (Addr = 0AH, 0BH)
(6) Set up REF value at ALC (Addr = 0CH)
(7) Set up IVOL value at ALC operation start (Addr = 0DH)
(8) Set up Auto HPF (Addr = 1AH)
(9) Programmable Filter ON/OFF Setting (Addr: 1BH, 1CH, 30H)
(10) Set up Programmable Filter Path: PFSDO bit = ADCPF bit = “1” (Addr = 1DH)
(11) Set up Coefficient Programmable Filter (Addr: 1EH ~ 2FH, 32H ~ 4FH)
(12) Power Up Microphone Amp, ADC and Programmable Filter: PMADL = PMADR =PMPFIL bits =
“0” → “1”
The initialization cycle time of ADC is 1059/fs=22ms @ fs=48kHz, ADRST1-0 bit = “00”. ADC
outputs “0” data during the initialization cycle. After the ALC bit is set to “1”, the ALC operation
starts from IVOL value of (7).
(13) Power Down Microphone Amp, ADC and Programmable Filter: PMADL = PMADR = PMPFIL bits
= “1” → “0”
(14) ALC Disable: ALC bit = “1” → “0”
016001936-E-00
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2016/03