AK4544A Datasheet, PDF (24/35 Pages) Asahi Kasei Microsystems – AC97 MULTIMEDIA AUDIO CODEC WITH SRC

[ASAHI KASEI]
[AK4544A]
n Audio Sample Rate control Registers (Index 2Ch, 32h)
Sample Rate controls for DACs, and ADC. 16bit data in D15(MSB) to D0 show unsigned value between 0 to 65535,
representing the exact sampling frequency in Hz. These Sample Rate setting is done at VRA=1 of Extended Audio
Status and Control Register(2Ah).
Sample Rate (kHz)
Data in D15 – D0
8.0
1F40 hex
11.025
2B11 hex
16.0
3E80 hex
22.05
5622 hex
32.0
7D00 hex
44.1
AC44 hex
48.0
BB80 hex
The AK4544A supports these discrete frequencies. When any other codes is written in this register, the AK4544A
works at the sampling rate rounded to the closest one above by decoding of only D15-D12 bits.
D15 – D12
Sample Rate (kHz)
0,1
8.0
2
11.025
3
16.0
4,5
22.05
6,7,8
32.0
9,Ah
44.1
Bh-Fh
48.0
At VRA=0, 2Ch and 32h are “BB80h” and can’t be written. When VRA is set to 0, 2Ch and 32h register are set to
“BB80h” automatically.
And the sample rate changing will be executed on the fly(immediately). It is recommended to set the zero data(no
input/no ouput) at the fs changing in order to prevent some noise.
n Vendor ID Registers (Index 7Ch, 7Eh)
This register is a read only register that is used to determine the specific vendor identification. The ID method is Microsoft Plug and
Play Vendor ID code with upper byte of 7Ch register, the first character of that id, lower byte of 7Ch register, the second character
and upper byte of 7Eh register the third character. These three characters are ASCII encoded. Lower byte of 7E register is for the
Vendor Revision number.
AKM’s vender ID is “AKM”, and revision number is 06 for AK4544A. As ASCII code “A” is 41h, “K” is 4Bh, and “M”
is 4Dh, Vendor ID registers are 414Bh and 4D06h respectively for AK4544A.
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