Cirrus Logic CS42L73 - Manual (Page 116)

116 DS882F1
CS42L73
6.44 ALC and Noise Gate Misc Control (Address 33h)
6.44.1 ALC Ganging of Channels A and B
Configures whether ALC for channels A and B is independent (see “ALC for Channels A and B (ALCx)”
on page 113 ) or ganged. If ganged, ALC is applied equally to channels A and B and is triggered by
• either channel A or B exceeding the ALC AB maximum threshold
or
• both channels A and B falling below the ALC AB minimum threshold ( “ALC Maximum
Threshold for Channels A and B” on page 114 and “ALC Minimum Threshold for Channels
A and B” on page 114 ).
Note: If ganged behavior is desired, set ALC_AB from 0b to 1b and then set ALCA and ALCB from 0b
to 1b simultaneously.
6.44.2 Noise Gate Ganging of Channels A and B
Configures whether noise gating for channels A and B will be independent (refer to “Noise Gate Enable
for Channels A and B (NGx)” on page 115 ) or ganged.
If ganged, noise gate muting is applied to both channels A and B when the signal amplitudes of both chan-
nels A and B are continuously below the noise gate AB minimum threshold (refer to
“Noise gate Threshold
and Boost for Channels A and B” on page 115 ) for longer than the attack delay (debounce) time (refer to
“Noise Gate Delay Timing for Channels A and B” on page 115 ).
Noise gate muting will be removed (released) without debouncing when either of the A or B signal levels
rise above the threshold.
Note: The noise gate attack and release rates (soft-ramped as a function of Fs or abrupt) are set ac-
cording to the programming of DIGSFT ( “Digital Soft-Ramp” on page 96 ).
6.44.3 ALCx Soft-Ramp Disable
Configures an override of the ALC Attack soft-ramp settings.
6.44.4 ALCx Zero Cross Disable
Configures an override of the ALC Attack Analog Zero Cross setting.
7 6 5 4 3 2 1 0
ALC_AB NG_AB ALCBSRDIS ALCBZCDIS ALCASRDIS ALCAZCDIS Reserved Reserved
ALC_AB ALC Status
0 Independent ALC on channels A and B
1 Ganged ALC for channels A and B
NG_AB Noise Gate triggered by:
0 Independent noise gating on channels A and B
1 Ganged noise gating on channels A and B
ALCxSRDIS ALC Soft-Ramp Disable
0 OFF; ALC Attack Rate is dictated by the DIGSFT ( “Digital Soft-Ramp” on page 96 ) and the PGASFT ( “PGA
Soft-Ramp” on page 95 ) settings
1 ON; ALC Attack volume changes take effect in one step, regardless of the DIGSFT or PGASFT settings
ALCxZCDIS ALC Zero Cross Disable
0 OFF; ALC Attack Rate is dictated by the ANLGZC ( “Analog Zero Cross” on page 95 ) setting
1 ON; ALC Attack volume changes take effect at any time, regardless of the ANLGZC setting