P 45, Cs43l21 – Cirrus Logic CS43L21 User Manual

Page 45

DS723F1

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.

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