
ASAHI KASEI 
[AK4683] 
MS0427-E-01 
2005/11 
- 41 - 
 Power ON/OFF Sequence 
The each block of the AK4683 are placed in the power-down mode by bringing PDN pin “L” and both digital filters are 
reset at the same time. PDN pin “L” also reset the control registers to their default values. In the power-down mode, the 
analog outputs go to VCOM voltage and SDTOA,B, DZF/OVF pin go to “L”. This reset should always be done after 
power-up.  
In slave mode, after exiting reset at power-up etc., the AK4683 starts to operate from the rising edge of LRCK after 
MLCK, then the device is in the power-down mode until MCLK and LRCK are input. In slave mode or Internal Loop 
Mode, the AK4683 starts to operate by the input of MLCK after exiting reset. 
The analog initialization cycle of ADC starts after exiting the power-down mode. Therefore, the output data, SDTO 
becomes available after 522/fs cycles of LRCK clock. In case of the DAC, an analog initialization cycle starts after 
exiting the power-down mode. The analog outputs are VCOM voltage during the initialization. Figure 23 hows the 
sequences of the power-down and the power-up.  
The ADC and all DACs can be powered-down individually by PWAD bit and PWDA1-2 bits. These bits don’t initialize 
the internal register values. When PWAD bit = “0” and selecting ADC, the SDTOA(SDTOB) pin goes to “L”. When 
PWDA1-2 bits = “0”, the analog outputs go to VCOM voltage and DZF/OVF pin go to “H”. Since some click noise 
may occur, the analog output should muted externally if the click noise influences system application. 
Power
ADC Internal 
  State
PDN
Clock In 
MCLK,LRCK,SCLK
ADC In 
 (Analog)
ADC Out 
 (Digital)
DAC Internal 
  State
DAC In 
 (Digital)
DAC Out 
 (Analog)
External 
 Mute
Mute ON 
(9) 
DZF1/DZF2
Power-down
Don’t care 
GD
“0”data
Power-down
“0”data
GD
(3)
(3)
(4) 
(6)
(7)
(8)
522/fs 
Init Cycle 
Normal Operation 
(1)
GD
Normal Operation 
GD
(5)
(6)
516/fs 
Init Cycle 
(2)
10
~
11/fs (10)
Mute ON 
“0”data 
“0”data 
Don’t care 
Notes: 
(1) The analog part of ADC is initialized after exiting the power-down state. 
(2) The analog part of DAC is initialized after exiting the power-down state. 
(3) Digital output corresponding to analog input and analog output corresponding to digital input have the group 
delay (GD). 
(4) ADC output is “0” data at the power-down state. 
(5) Click noise occurs at the end of initialization of the analog part. Please mute the digital output externally if the 
click noise influences system application.  
(6) Click noise occurs at the falling edge of PDN and at 512/fs(DAC1) and 512/fs +96ms(DAC2) after the rising 
edge of PDN. 
(7) When the external clocks 
(MCLK, BICKA (BICKB), LRCKA (LRCKB))
 are stopped, the AK4683 should be in the 
power-down mode. 
(8) DZF/OVF pin is “L” in the power-down mode (PDN pin = “L”). 
(9) Please mute the analog output externally if the click noise (6) influences system application. 
(10) DZF pin = “L” for 10
~
11/fs after PDN= “
↑
”. 
Figure 23. Power-down/up sequence example