AD1845

–18–

REV. C

RX2A4:0

Right Auxiliary Input #2 Attenuate Select. The least significant bit of this gain/attenuate select represents

1.5 dB. RX2A4:0 = 0 produces a +12 dB gain. RX2A4:0 = “01000” (8 decimal) produces 0 dB gain.

Maximum attenuation is –34.5 dB. See Figure 10.

res

Reserved for future expansion. Always write zeros to these bits.

RMX2

Right Auxiliary #2 Mute. This bit, when set, will mute the right channel of the Auxiliary #2 input source. This bit

powers up set.

This register’s initial state after reset is “1xx0 1000.”

Left DAC Control (IXA3:0 = 6)

IXA3:0

Data 7

Data 6

Data 5

Data 4

Data 3

Data 2

Data 1

Data 0

6

LDM

res

LDA5

LDA4

LDA3

LDA2

LDA1

LDA0

LDA5:0

Left DAC Attenuate Select. The least significant bit of this gain/attenuate select represents 1.5 dB. Maximum

attenuation is –94.5 dB. See Figure 7.

res

Reserved for future expansion. Always write a zero to this bit.

LDM

Left DAC Mute. This bit, when set to 1, will mute the left DAC output. This bit powers up active.

This register’s initial state after reset is “1x00 0000.”

Right DAC Control (IXA3:0 = 7)

IXA3:0

Data 7

Data 6

Data 5

Data 4

Data 3

Data 2

Data 1

Data 0

7

RDM

res

RDA5

RDA4

RDA3

RDA2

RDA1

RDA0

RDA5:0

Right DAC Attenuate Select. The least significant bit of this gain/attenuate select represents 1.5 dB. Maximum

attenuation is –94.5 dB. See Figure 7.

res

Reserved for future expansion. Always write a zero to this bit.

RDM

Right DAC Mute. This bit, when set to 1, will mute the right DAC output. This bit powers up active.

This register’s initial state after reset is “1x00 0000.”

A5

A4

A3

A2

A1

A0

Mix Gain

000000

000001

000010

000011

000100

000101

000110

000111

–10.5 dB

001000

–12.0 dB

001001

–13.5 dB

001010

–15.0 dB

001011

–16.5 dB

•

•••••

•

•

•••••

•

•

•••••

•

110100– 78.0 dB

110101– 79.5 dB

110110– 81.0 dB

110111– 82.5 dB

111000– 84.0 dB

111001– 85.5 dB

111010– 87.0 dB

111011– 88.5 dB

111100– 90.0 dB

111101– 91.5 dB

111110– 93.0 dB

111111– 94.5 dB

Figure 7. Mix Gain Level Setting: DAC