Clock and Data Recovery

SCKO

BCKO

LRCKO

DOUT

RXIN

Divider

FILT

XTO

XTI

FSOUT0

FSOUT1

OSC

CLKST

VCO

CKSEL

DGND

ERROR

PLL

Divider

Decoder

Preamble

Detector

Charge

Pump

Clock

Decoder

Biphase

Data Decoder

Serial

AudioData

Formatter

ERROR

Detector

AudioData

MUTE Control

Sampling

Frequency

Calculator

DIR9001

www.ti.com

SLES198A – DECEMBER 2006 – REVISED MAY 2015

Device Functional Modes (continued)

The details of these three modes are given in Table 12.

Table 12. Operation Mode and Clock Source

ERROR

OPERATION

CKSEL PIN

SCKO, BCKO, LRCKO

AUDIO

FSOUT

COUT

PIN

DOUT DATA

BFRAME

MODE

SETTING

CLOCK SOURCE

EMPH

[1:0]

UOUT

STATUS

PLL (VCO) free-running

H

MUTE (Low)

LOW

HL

LOW

LOW

clock(1)

PLL

L

L

PLL recovered clock

Decoded data

OUT

OUT

OUT

OUT

H

XTI clock

MUTE (Low)

LOW

HL

LOW

LOW

XTI

H

L

XTI clock

MUTE (Low)

OUT

OUT

OUT

LOW

H

XTI clock

MUTE (Low)

LOW

HL

LOW

LOW

Connected to

AUTO

ERROR pin

L

PLL recovered clock

Decoded data

OUT

OUT

OUT

OUT

(1)

The VCO free-running frequency is not a constant frequency, because the VCO oscillation frequency is dependent on supply voltage,

temperature, and process variations.

Figure 12. Clock Source, Source Selector and Data Path

8.4.1.2 Clock Transition Signal Out

The DIR9001 provides an output pulse that is synchronized with the PLL’s LOCK/UNLOCK status change.

The CLKST pin outputs the PLL status change between LOCK and UNLOCK. The CLKST output pulse depends

only on the status change of the PLL.

This clock change/transition signal is output through CLKST.

As this signal indicates a clock transition period due to a PLL status change, it can be used for muting or other

appropriate functions in an application.

A clock source selection caused by the CLKSEL pin does not affect the output of CLKST.

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