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MODE CONTROL REGISTERS

USER-PROGRAMMABLE MODE CONTROLS

REGISTER MAP

RESERVED REGISTERS

PCM1680

SLES133 – MARCH 2005

The PCM1680 includes a number of user-programmable functions which are accessed via control registers. The

registers are programmed using the serial control interface which is discussed in the Mode Control section of this

data sheet. Table 5 lists the available mode control functions, along with their reset default conditions and

associated register index.

The mode control register map is shown in Table 6. The MSB of all registers is fixed to 0. Each register also

includes an index (or address) indicated by the IDX[6:0] bits.

Registers 0, 11, and 15 are reserved for factory use. To ensure proper operation, the user should not write to

these registers.

Table 5. User-Programmable Mode Controls

FUNCTION

RESET DEFAULT

REGISTER

BIT

Digital attenuation control, 0 dB to –63 dB 0 dB, no attenuation

1–6, 16, 17

AT1[7:0], AT2[7:0], AT3[7:0], AT4[7:0],

in 0.5-dB steps

AT5[7:0], AT6[7:0], AT7[7:0], AT8[7:0]

Soft mute control

Mute disabled

7, 18

MUT[6:1], MUT[8:7]

DAC1–DAC8 operation control

DAC1–DAC8 enabled

8, 19

DAC[6:1], DAC[8:7]

Audio data format control

24-bit, left-justified

9

FMT[2:0]

Digital filter rolloff control

Sharp rolloff

9

FLT

De-emphasis all-channel function control

De-emphasis of all channels

10

DMC

disabled

De-emphasis all-channel sample rate

44.1 kHz

10

DMF[1:0]

selection

Output phase select

Normal phase

10

DREV

Zero-flag polarity select

High

10

ZREV

Software reset control

Reset disabled

10

SRST

Oversampling rate control

×64, ×32, ×16

12

OVER

Zero-flag combination select

ZERO1: DATA1 Lch

13

AZRO[1:0]

ZERO2: DATA1 Rch

Digital attenuation mode select

0 to –63 dB, 0.5-dB step

13

DAMS

N/A

14

ZERO[8:1]

interface only)

21