PCM1606

SLES014B − OCTOBER 2001 − REVISED AUGUST 2002

12

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functional description (continued)

de-emphasis control

The de-emphasis control can be selected by DEMP1 (pin 17) and DEMP0 (pin 16). See Table 5.

Table 5. De-Emphasis Control

DEMT1 (pin 17)

DEMT0 (pin 16)

AUDIO INTERFACE

LOW

LOW

OFF

LOW

HIGH

48 kHz

HIGH

LOW

44.1 kHz

HIGH

HIGH

32 kHz

analog outputs

outputs, each capable of driving 3.1 Vp-p typical into a 5-k

The output amplifiers include an RC continuous-time filter, which helps to reduce the out-of-band noise energy

present at the DAC outputs due to the noise shaping characteristics of the PCM1606’s delta-sigma D/A

converters. The frequency response of this filter is shown in Figure 7. By itself, this filter is not enough to

attenuate the out-of-band noise to an acceptable level for most applications. An external low-pass filter is

required to provide sufficient out-of-band noise rejection. Further discussion of DAC post-filter circuits is

provided in the Application Information section of this data sheet.

f − Frequency − Hz

−100

−80

−60

−40

−20

0

20

LEVEL

vs

FREQUENCY

110

100

1k

10k

100k

1M

10M

Figure 7. Output Filter Frequency Response