CS42L51 Datasheet, PDF (70/83 Pages) Cirrus Logic – Low Power, Stereo CODEC with Headphone Amp

CS42L51
6.26 Noise Gate Configuration & Misc. (Address 1Fh)
7
NG_ALL
6
NG_EN
5
4
NG_BOOST THRESH2
3
THRESH1
2
THRESH0
1
0
NGDELAY1 NGDELAY0
Noise Gate Channel Gang (NG_ALL)
Default: 0
0 - Disabled
1 - Enabled
Function:
Gangs the noise gate function for channel A and B. When enabled, both channels must fall below the thresh-
old setting for the noise gate attenuation to take effect.
Noise Gate Enable (NG_EN)
Default: 0
0 - Disabled
1 - Enabled
Function:
Enables the noise gate. Maximum attenuation is relative to all gain settings applied.
Noise Gate Boost (NG_BOOST) and Threshold (THRESH[3:0])
Default: 000
THRESH[2:0]
000
001
010
011
100
101
110
111
Minimum Setting
(NG_BOOST = ‘0’b)
-64 dB
-67 dB
-70 dB
-73 dB
-76 dB
-82 dB
Reserved
Reserved
Minimum Setting
(NG_BOOST = ‘1’b)
-34 dB
-37 dB
-40 dB
-43 dB
-46 dB
-52 dB
-58 dB
-64 dB
Function:
Sets the threshold level of the noise gate. Input signals below the threshold level will be attenuated to -96
dB. NG_BOOST = ‘1’b adds 30 dB to the threshold settings.
Noise Gate Delay Timing (NGDELAY[1:0])
Default: 00
00 - 50 ms
01 - 100 ms
10 - 150 ms
11 - 200 ms
Function:
Sets the delay time before the noise gate attacks. Noise gate attenuation is dictated by the SOFTx &
ZCROSS bit settings unless the disable bit for each function is enabled.
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