BU9414FV Datasheet, PDF (55/61 Pages) Rohm – 32bit Audio DSP

BU9414FV
Technical Note
14. Notes at the Time of Reset
Since the state of IC is not decided, please make it into RESETX=L at the time of a power supply injection, and surely apply
reset.
Reset of BU9414FV is performing noise removal by MCLK.
Therefore, in order to apply reset, a MCLK clock pulse is required of the state of RESETX=L more than 10 times.
The power-on reset after a power supply injection, and when you usually apply reset at the time of operation, please be sure
to carry out in the state where the clock is inputted, from MCLK.
15. Read-out of Soft Transition Flag
It is set to &hF4[0] =H, &hFD[0]=H when BASS, MIDDLE, TREBLE or P2Bass, and P2Treble are soft transiting.
It is possible to check whether soft transition is completed by reading &hF4 [0]or &hFD[0]
Soft transition will be completed if the read-out result of &hF4 [0] or &hFD [0] is L.
16. Data taking-in position adjustment circuit
There is a circuit which adjusts the position of data taking in so that data can be received, even when the incoming signal is
shaking by jitter.
DSP clock use multiplied input clock by PLL.
Even when I2S signal inputted is shaking by jitter, the taking-in position of data is adjusted to the position which has a margin
most so that take data and they may not be spilt.
Adjust a data taking-in position by making it &hAA[7] =H.
The read-out value of &hAA[7] is set to H during adjustment of a data taking-in position.
It reads, after adjustment of a data taking-in position finishes, and a value is set to L.
The reset release back, the time of an input sampling rate change, etc. adjust, when the lock state of PLL changes.
Please refer to the recommendation procedure of Chapter 8 and Chapter 11 for details.
When there is no margin in the data taking-in position of DSP, the read-out value of &hAA[3] is set to H.
& Once hAA [3] is set to H, it will read until it adjusts a data taking-in position or writes 0 in &hAA[3], and a value will not be set
to L.
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2012.03 - Rev.A