Datasheet
DREV: Output Phase Select
DMF[1:0]: Sampling Frequency Selection for the De-Emphasis Function
DMC: Digital De-Emphasis All-Channel Function Control
OVER: Oversampling Rate Control
PCM1680
SLES133B – MARCH 2005 – REVISED OCTOBER 2008 ..................................................................................................................................................
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Default value: 0
DREV = 0 Normal output (default)
DREV = 1 Inverted output
The DREV bit is the output analog signal phase control.
Default value: 00b
DMF[1:0] De-Emphasis Sampling Rate Selection
00 44.1 kHz (default)
01 48 kHz
10 32 kHz
11 Reserved
The DMF[1:0] bits select the sampling frequency used for the digital de-emphasis function when it is enabled.
The de-emphasis curves are shown in the Typical Characteristics section of this data sheet. The preceding table
shows the available sampling frequencies.
Default value: 0
DMC = 0 De-emphasis disabled for all channels (default)
DMC = 1 De-emphasis enabled for all channels
The DMC bit is used to enable or disable the de-emphasis function for all channels.
B15 B14 B13 B12 B11 B10 B9 B8 B7 B6 B5 B4 B3 B2 B1 B0
REGISTER 12 0 IDX6 IDX5 IDX4 IDX3 IDX2 IDX1 IDX0 OVER RSV RSV RSV RSV RSV RSV RSV
Default value: 0
System clock frequency = 512 f
S
, 768 f
S
, or 1152 f
S
OVER = 0 x64 oversampling (default)
OVER = 1 x128 oversampling (applicable only if sampling clock frequency ≤ 24 kHz)
System clock frequency = 256 f
S
or 384 f
S
OVER = 0 x32 oversampling (default)
OVER = 1 x64 oversampling (applicable only if sampling clock frequency ≤ 48 kHz)
System clock frequency = 128 f
S
or 192 f
S
.
OVER = 0 x16 oversampling (default)
OVER = 1 x32 oversampling (applicable only if sampling clock frequency ≤ 96 kHz)
The OVER bit is used to control the oversampling rate of the Δ Σ DACs.
Setting OVER = 1 is recommended under the following conditions:
• System clock frequency = 512 f
S
, 768 f
S
, or 1152 f
S
and sampling clock frequency ≤ 24 kHz
• System clock frequency = 256 f
S
or 384 f
S
and sampling clock frequency ≤ 48 kHz
• System clock frequency = 128 f
S
or 192 f
S
and sampling clock frequency ≤ 96 kHz
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