AD1980 Analog Devices, AD1980 Datasheet - Page 11

• Manufacturer Part Number: AD1980
• Description: AD1980 AC'97 SoundMAX® Codec W/spdif W/eq
• Manufacturer: Analog Devices

*For AC ’97 compatibility, Bit D7 is available only by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right
Reg. 76h
MSPLT* D15 WRITE
0
0
0
0
0
1
1
1
*For AC ’97 compatibility, Bit D7 is available only by setting the MSPLT bit, Register 76h. The MSPLT bit enables separate mute bits for the left and right
*Refer to Table II for examples. This register controls the Mono output volume and mute bit. The volume register contains five bits, generating 32 volume levels with
MV[5:0]
MVM
REV. 0
Reg
No. Name
04h
channels. If MSPLT is not set, Bit D7 has no effect.
Reg
No. Name
06h
31 steps of 1.5 dB each. Because AC ’97 defines 6-bit volume registers, to maintain compatibility, whenever the D5 bit is set to “1,” their respective lower five vol-
ume bits are automatically set to “1” by the codec logic. On readback, all lower five bits will read “1s” whenever this bit is set to “1.” All registers not shown and bits
containing an X are assumed to be reserved.
channels. If MSPLT is not set, Bit D7 has no effect.
x in the above table is “don’t care.”
Headphones
Volume
Mono Volume MVM
0
0
0
0
1
0
1
1
Mono Volume Control. The least significant bit represents 1.5 dB. This register controls the output from 0 dB to a
maximum attenuation of 46.5 dB.
Mono Volume Mute. When this bit is set to “1,” the channel is muted.
00 0000
00 1111
01 1111
1x xxxx
xx xxxx
1x xxxx
xx xxxx
xx xxxx
D15
HPM
D15
Left Channel Volume D[13:8]
D14
X
D14 D13
X
D15
0
0
0
1
x in the above table is a wild card and has no effect on the value.
READBACK Function
00 0000
00 1111
01 1111
01 1111
xx xxxx
01 1111
xx xxxx
xx xxxx
D13
LHV5 LHV4 LHV3 LHV2 LHV1 LHV0 HPRM* X
X
D12
Table I. Volume Settings for Master and Headphone
D12
X
Control Bits D[4:0] for Mono (06h)
WRITE
0 0000
0 1111
1 1111
x xxxx
Master Volume (02h) and Headphone Volume (04h)
Headphones Volume Register (Index 04h)
D11
0 dB Gain
–22.5 dB Gain
–46.5 dB Gain
–46.5 dB Gain
– dB Gain, Muted
–46.5 dB Gain
– dB Gain, Left only Muted
– dB Gain, Left Muted
D11
X
Table II. Volume Settings for Mono
Mono Volume Register (Index 06h)
D10
D10
X
D9
D9
X
READBACK
0 0000
0 1111
1 1111
x xxxx
–11–
D8
Control Bits
D8
X
D7
D7
X
D6
X
D6 D5
D7* WRITE READBACK
x
x
x
x
x
1
0
1
D5*
MV5
RHV5 RHV4 RHV3 RHV2
Function
0 dB Gain
–22.5 dB Gain
–46.5 dB Gain
– dB Gain, Muted
Right Channel Volume D[5:0]
00 0000 00 0000
00 1111 00 1111
01 1111 01 1111
1x xxxx
xx xxxx
xx xxxx
xx xxxx
xx xxxx
D4
MV4
D4
D3
01 1111
xx xxxx
xx xxxx
xx xxxx
xx xxxx
D3
MV3
D2
D2
MV2
D1
RHV1 RHV0 8000h
D1
MV1
Function
0 dB Gain
–22.5 dB Gain
–46.5 dB Gain
–46.5 dB Gain
– dB Gain, Muted
– dB Gain, only
Right Muted
–46.5 dB Gain
– dB Gain, Right
Muted
AD1980
D0
D0
MV0
Default
Default
8000h