IS31AP2121
Integrated Silicon Solution, Inc. – www.issi.com
29
Rev. C, 10/20/2015
D1~ D0. When noise gate function occurs, input
signal will multiply noise gate gain (x1/8, x1/4 x1/2,
x0). User can select fade out or not via D4.
A_SEL_FAULT
I2C Address Selection or ERROR
output
0 I2C
address
selection
1 ERROR
output
D_MOD
Delta Quaternary Modulation
0 Disable
1 Enable
DIS_NG_FADE
Disable Noise Gate Fade
0 Fade
1 No
fade
NG_GAIN
Noise Gate Gain
00 x1/8
01 x1/4
10 x1/2
11 Mute
Table 19 14h Coefficient RAM Base Address
Register
Bit
D7
D6:D0
Name -
CFA
Default x
000
0000
An on-chip RAM in IS31AP2121 stores user-defined
EQ and mixing coefficients. The content of this
coefficient RAM is indirectly accessed via coefficient
registers, which consist of one base address register
(14h), five sets of registers (15h ~ 23h) of three
consecutive 8-bit entries for each 24-bit coefficient,
and one control register (24h) to control access of
the coefficients in the RAM.
CFA
Coefficient RAM Base Address
Table 20 15h~17h User-Defined Coefficients
Registers
(Top/Middle/Bottom 8-bits of coefficients A1)
Bit
D7:D0
Name C1B
Default -
Table 21 18h~1Ah User-Defined Coefficients
Registers
(Top/Middle/Bottom 8-bits of coefficients A2)
Bit
D7:D0
Name C2B
Default -
Table 22 1Bh~1Dh User-Defined Coefficients
Registers
(Top/Middle/Bottom 8-bits of coefficients A1)
Bit
D7:D0
Name C3B
Default -
Table 23 1Eh~20h User-Defined Coefficients
Registers
(Top/Middle/Bottom 8-bits of coefficients B2)
Bit
D7:D0
Name C4B
Default -
Table 24 21h~23h User-Defined Coefficients
Registers
(Top/Middle/Bottom 8-bits of coefficients A0)
Bit
D7:D0
Name C5B
Default -
Table 25 24h Coefficients Control Register
Bit
D7:D4
D3
D2
D1
D0
Name - RA R1 WA W1
Default xxxx 0
0
0
0
RA
Enable of Reading a Set of Coefficients from
RAM
0 Read
complete
1 Read
enable
R1
Enable of Reading a Single Coefficient from
RAM
0 Read
complete
1 Read
enable
WA
Enable of Writing a Set of Coefficients to
RAM
0 Write
complete
1 Write
enable
W1
Enable of Writing a Single Coefficient to
RAM
0 Write
complete
1 Write
enable