AK4128A Datasheet, PDF (37/50 Pages) Asahi Kasei Microsystems – 8ch 216kHz / 24-Bit Asynchronous SRC

[AK4128A]
■ Internal Status Pin
The UNLOCK pin indicates internal status of the device. This pin outputs “H” when the PDN pin = “L”. SRC data is output
from SDTO1-4 pins, which corresponds to the each sampling frequency ratio detected SRC, after a rising edge “↑” of PDN
if the internal regulator is in normal operation. In 8-channel mode, the UNLOCK pin outputs “L” when sampling frequency
ratio detection is completed at all SRC’s (SRC1-4). The UNLOCK pin keeps outputting “H” if there is one SRC which
does not finished sampling frequency ratio detection.
In 6-channel mode, the UNLOCK pin outputs “L” when sampling frequency ratio detection is completed at SRC1-3. It
keeps outputting “H” if there is one SRC which does not finish sampling frequency ratio detection.
In 4-channel mode, the UNLOCK pin outputs “L” when sampling frequency ratio detection is completed at SRC1-2. It
keeps outputting “H” if there is one SRC which does not finish sampling frequency ratio detection.
When over-current/voltage is flowed at the internal regulator, the UNLCOK pin outputs “H”. An OR’ed result of the flags
between over-current/voltage detection at the internal regulator and SRC sampling frequency detection complete is output
from this pin.
Over-Current/Voltage Limit Flag
(“L” Normal, “H” Over-Current/Voltage detect)
SRC Sampling Frequency Ratio Complete Flag
UNLOCK pin
Figure 38. Internal Flags and UNLOCK pin Output
In parallel control mode, if the AK4128A is set in SRC bypass mode by CM2-0 pins during the PDN pin = “L” and
powered-up, the UNLOCK pin outputs “L” after the power-up time of the internal regulator (max. 1.4ms) from a rising
edge “↑” of the PDN pin. In serial control mode, if BYPS bit is set to “1”while RSTN bit = “0”, the UNLOCK pin
immediately outputs “L” after the register writing.
MS1242-E-00
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2010/09