cs44600 Cirrus Logic, Inc., cs44600 Datasheet - Page 53

• Manufacturer Part Number: cs44600
• Description: 6-channel Digital Amplifier Controller
• Manufacturer: Cirrus Logic, Inc.

DS633F1
7.7
7.7.1
7.7.2
7.7.3
SNGVOL
7
Volume Control Configuration (address 06h)
Single Volume Control (SNGVOL)
Default = 0
Function:
The individual channel volume levels are independently controlled by their respective Volume Control reg-
isters when this function is disabled. When enabled, the volume on all channels is determined by the A1
Channel Volume Control register. The other Volume Control registers are ignored.
Soft Ramp and Zero Cross Control (SZC[1:0])
Default = 10
00 - Immediate Change
01 - Zero Cross
10 - Soft Ramp
11 - Soft Ramp on Zero Crossings
Function:
Immediate Change
When Immediate Change is selected, all level changes will take effect immediately in one step.
Zero Cross
Zero Cross Enable dictates that signal level changes, either by attenuation changes or muting, will occur
on a signal zero crossing to minimize audible artifacts. The requested level change will occur after a tim-
eout period (approximately 18.7 ms for a PWM switch rate of 384/768 kHz and 17.0 ms for a PWM switch
rate of 421.875/843.75 kHz) if the signal does not encounter a zero crossing. The zero cross function is
independently monitored and implemented for each channel.
Soft Ramp
Soft Ramp allows level changes, both muting and attenuation, to be implemented by incrementally ramp-
ing, in 1/8 dB steps, from the current level to the new level at a rate of 1 dB per 8 left/right clock periods.
Soft Ramp on Zero Crossing
Soft Ramp and Zero Cross Enable dictates that signal level changes, either by 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 (approximately 18.7 ms for a PWM switch rate of 384/768 kHz and
17.0 ms for a PWM switch rate of 421.875/843.75 kHz) if the signal does not encounter a zero crossing.
The zero cross function is independently monitored and implemented for each channel.
Enable 50% Duty Cycle for Mute Condition (MUTE_50/50)
Default = 0
0 - Disabled
1 - Enabled
Function:
This bit enables the modulator to output an exact 50%-duty-cycle PWM signal (not modulated), which cor-
responds to digital silence, for all mute conditions. The muting function is affected, similar to volume con-
SZC1
6
SZC0
5
RESERVED
4
MUTE_50/50
3
SRD_ERR
2
SRU_ERR
1
CS44600
AMUTE
0
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