Cirrus Logic CS43L22 - Manual (Page 42)

42 DS792F2
CS43L22
Confidential Draft
3/4/10
7.7 Passthrough x Select: PassA (Address 08h), PassB (Address 09h)
7.7.1 Passthrough Input Channel Mapping
Selects one or sums/mixes the analog input signal into the passthrough Amplifier. Each bit of the
PASSx_SEL[4:1] word corresponds to individual channels (i.e. PASSx_SEL1 selects AIN1x,
PASSx_SEL2 selects AIN2x, etc.).
7.8 Analog ZC and SR Settings (Address 0Ah)
7.8.1 Ch. x Analog Soft Ramp
Configures an incremental volume ramp from the current level to the new level at the specified rate.
7.8.2 Ch. x Analog Zero Cross
Configures when the signal level changes occur for the analog volume controls.
Note: If the signal does not encounter a zero crossing, the requested volume change will occur after a
timeout period of 1024 sample periods (approximately 10.7 ms at 48 kHz sample rate).
7.9 Passthrough Gang Control (Address 0Ch)
7.9.1 Passthrough Channel B=A Gang Control
Configures independent or ganged control of the passthrough channel settings. Mute is not affected.
7 6 5 4 3 2 1 0
Reserved Reserved Reserved Reserved PASSASEL4 PASSASEL3 PASSASEL2 PASSASEL1
PASSxSEL[4:1] Selected Input to Passthrough Channel x
00000 No inputs selected
00001 AIN1x
00010 AIN2x
00100 AIN3x
01000 AIN4x
Application: “Analog Passthrough” on page 24
Note: Table does not show all possible combinations.
7 6 5 4 3 2 1 0
Reserved Reserved Reserved Reserved ANLGSFTB ANLGZCB ANLGSFTA ANLGZCA
ANLGSFTx Volume Changes Affected Analog Volume Controls
0 Do not occur with a soft ramp
PASSxVOL[7:0] ( “Passthrough x Volume” on page 46 )
1 Occur with a soft ramp
Ramp Rate: 1/2 dB every 16 LRCK cycles
ANLGZCx Volume Changes Affected Analog Volume Controls
0
Do not occur on a zero cross-
ing
PASSxVOL[7:0] ( “Passthrough x Volume” on page 46 )
1 Occur on a zero crossing
7 6 5 4 3 2 1 0
PASSB=A Reserved Reserved Reserved Reserved Reserved Reserved Reserved
PASSB=A Single Volume Control
0 Disabled
1 Enabled