32

DS691A3

CS4350

8.6

Ramp and Filter Control - Register 07h

8.6.1

Soft Ramp and Zero Cross Control (SZC[1:0]) Bits 7-6

Default = 10

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 time-

out 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 implemented

for each channel.

Soft Ramp PCM

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 and Zero Cross

Soft Ramp and Zero Cross Enable dictate that signal level changes, either by attenuation changes or mut-

ing, 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 time-out 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 implemented for each channel.

Binary Code

Decimal Value

Volume Setting

00000000

0

0 dB

00000001

1

-0.5 dB

00000110

6

-3.0 dB

11111111

255

-127.5 dB

Table 6. Example Digital Volume Settings

76

543

21

0

SZC1

SZC0

RMP_UP

RMP_DN

Reserved

FILT_SEL

Reserved

Reserved

10

110

00

1

SZC1 SZC0

Description

0

0

Immediate Change

01

Zero Cross

1

0

Soft Ramp

1

1

Soft Ramp on Zero Crossings