AD1980 Analog Devices, AD1980 Datasheet - Page 17

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

The ready bits are read only; writing to REF, ANL, DAC, ADC will have no effect. These bits indicate the status for the AD1980 subsections. If the bit is a 1, then
that subsection is ready. Ready is defined as the subsection able to perform in its nominal state. All registers not shown and bits containing an X are assumed to be reserved.
ADC
DAC
ANL
REF
PR[6:0]
EAPD
REV. 0
Reg
No. Name
26h Power-Down
Control/Status
Codec Power-Down Modes. The first three bits are to be used individually rather than in combination with each
ADC Sections Ready to Transmit Data
DAC Sections Ready to Transmit Data
Analog Amplifiers, Attenuators and Mixers Ready
Voltage References, V
other. PR3 can be used in combination with PR2 or by itself. The mixer and reference cannot be powered down via
PR3 unless the ADCs and DACs are also powered down. Nothing else can be powered up until the reference is up.
PR5 has no effect unless all ADCs, DACs, and the AC-Link are powered down. The reference and the mixer can be
either up or down, but all power-up sequences must be allowed to run to completion before PR5 and PR4 are both set.
In multiple codec systems, the master codec’s PR5 and PR4 bits control the slave codec. PR5 is also effective in the
slave codec if the master’s PR5 bit is clear, but the PR4 bit has no effect except to enable or disable PR5.
External Audio Power-Down Control. Controls the state of the EAPD pin.
EAPD = 0 sets the EAPD pin low, enabling an external power amplifier (reset defaults).
EAPD = 1 sets the EAPD pin high, shutting off the external power amplifier.
D15
EAPD PR6
D14
REF
D13 D12
PR5 PR4
Power-Down Control/Status Register (Index 26h)
and V
REFOUT
PR3
D11
up to Nominal Level
D10
PR2
D9
PR1
–17–
D8
PR0
D7
X
D6
X
D5
X
D4
X
REF
D3
D2
ANL DAC ADC NA
D1
AD1980
D0
Default