Cirrus Logic CS43L21 - Manual (Page 45)

DS723F1 45
CS43L21
Soft Ramp
Soft Ramp allows level changes, either by gain changes, attenuation changes or muting, to be implemented
by incrementally ramping, in 1/8 dB steps, from the current level to the new level at a rate of 0.5 dB per 4
left/right clock periods.
Soft Ramp on Zero Crossing
This setting dictates that signal-level changes, either by gain changes, attenuation changes or muting, will
occur in 1/8 dB steps and be implemented on a signal zero crossing. The 1/8 dB level change will occur
after a timeout period between 512 and 1024 sample periods (10.7 ms to 21.3 ms at 48 kHz sample rate) if
the signal does not encounter a zero crossing. The zero cross function is independently monitored and im-
plemented for each channel. Note: The LIM_SRDIS bit is ignored.
6.7 PCMX Mixer Volume Control:
PCMA (Address 10h) & PCMB (Address 11h)
Note: The DATA_SEL[1:0] bits in reg09h must be set to ‘01’b to enable function control in this register.
PCMX Mixer Channel Mute (MUTE_PCMMIXX)
Default = 1
0 - Disabled
1 - Enabled
Function:
The PCM channel X input to the output mixer will mute when enabled. The muting function is affected by
the DACX Soft and Zero Cross bits (DACX_SZC[1:0]).
PCMX Mixer Volume Control (PCMMIXX_VOL[6:0])
Default: 000 0000
Function:
The level of the PCMX input to the output mixer can be adjusted in 0.5 dB increments as dictated by the
DACX Soft and Zero Cross bits (DACX_SZC[1:0]) from +12 to -51.5 dB. Levels are decoded as described
in the table above.
7 6 5 4 3 2 1 0
MUTE_
PCMMIXx
PCMMIXx_
VOL6
PCMMIXx_
VOL5
PCMMIXx_
VOL4
PCMMIXx_
VOL3
PCMMIXx_
VOL2
PCMMIXx_
VOL1
PCMMIXx_
VOL0
Binary Code Volume Setting
001 1000 +12.0 dB
··· ···
000 0000 0 dB
111 1111 -0.5 dB
111 1110 -1.0 dB
··· ···
001 1001 -51.5 dB