AD1981B

Rev. C | Page 18 of 32

PCM-OUT VOLUME REGISTER

Index 0x18

Reg

No.

Name

D15

D14

D13

D12

D11

D10

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

Default

0x18

PCM-Out

Volume

OM

X

X

LOV4

LOV3

LOV2

LOV1

LOV0

RM1

X

X

ROV4

ROV3

ROV2

ROV1

ROV0

0x8808

If MSPLT is not set, the RM bit has no effect. All registers are not shown, and bits containing an X are assumed to be reserved. Refer to

for examples.

Table 22

Table 21.

Bit

Mnemonic

Function

ROV [4:0]

Right PCM-Out Volume

Allows setting the PCM right-channel attenuator in 32 volume levels. The LSB represents 1.5 dB, and

the range is +12 dB to −34.5 dB. The default value is 0 dB, mute enabled.

RM

Right-Channel Mute

Once enabled by the MSPLT bit in Register 0x76, this bit mutes the right channel separately from

the OM bit. Otherwise, this bit always reads 0 and has no effect when set to 1.

LOV [4:0]

Left PCM-Out Volume

Allows setting the PCM left-channel attenuator in 32 volume levels. The LSB represents 1.5 dB, and

the range is +12 dB to −34.5 dB. The default value is 0 dB, mute enabled.

OM

PCM-Out Volume Mute

When this bit is set to 1, both the left and right channels are muted unless the MSPLT bit in

Register 0x76 is set to 1, in which case this mute bit affects only the left channel.

Table 22. Volume Settings for Line-In, CD Volume, AUX, and PCM-Out

Control Bits

Reg. 0x76

Line-In (0x10), CD (0x12), AUX (0x16), and PCM-Out (0x18)

Left-Channel Volume D [12:8]

Right-Channel Volume D [4:0]

MSPLT1

D15

Write

Readback

Function

D71

Write

Readback

Function

0

0

0 0000

0 0000

+12 dB Gain

X

0 0000

0 0000

+12 dB Gain

0

0

0 1000

0 1000

0 dB Gain

X

0 1000

0 1000

0 dB Gain

0

0

1 1111

1 1111

+34.5 dB

Gain

X

1 1111

1 1111

−34.5 dB

Gain

0

1

X XXXX

X XXXX

−∞ dB Gain,

Muted

X

X XXXX

X XXXX

−∞ dB Gain,

Muted

1

0

1 1111

1 1111

−34.5 dB

Gain

1

X XXXX

X XXXX

−∞ dB Gain,

Right Only

Muted

1

1

X XXXX

X XXXX

−∞ dB Gain,

Left Only

Muted

0

1 1111

1 1111

−34.5 dB

Gain

1

1

X XXXX

X XXXX

−∞ dB Gain,

Left Muted

1

X XXXX

X XXXX

−∞ dB Gain,

Right Muted

If MSPLT is not set, the RM bit has no effect.

X is a wild card and has no effect on the value.