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16

PCM1721

AC-3 APPLICATION CIRCUIT

A typical application for PCM1721 is AC-3 5.1 channel audio decoding and playback. This circuit uses PCM1721 to develop

the audio system clock from the 27MHz video clock, with the SCKO pin used to drive the AC-3 decoder and two PCM1720

units, the non-PLL version of PCM1721.

FIGURE 17. Connection Diagram for a 6-Channel AC-3 Application.

14

16

15

2

SCKO

LRCKO

SERO_0

SERO_1

SERO_2

SYSCKI

BCKIN

LRCIN

DIN

SCKI

ML

MC

MD

RSTB

V

CAP

V

ZERO

Master Clock

Generator

or

PLL

Reset

µP

STRB

SCKO

SDO

+5V Analog

Post

Low Pass

Filter

10µF

+

Three-wire I/F

(Serial I/O)

3

20

PCM1720

PCM1720

PCM1721

19

DGND

AC-3

Audio

Decoder

V

DD

AGND

V

CC

4

5

6

7

9

8

12

13

Analog

Mute

Analog Out

Post

Low Pass

Filter

Analog

Mute

Analog Out

Mute

Control

+5V Analog

10

11

14

16

15

2

BCKIN

LRCIN

DIN

SCKI

ML

MC

MD

RSTB

V

CAP

V

ZERO

+5V Analog

Post

Low Pass

Filter

10µF

+

20

19

DGND

V

DD

AGND

V

CC

4

5

6

7

9

8

12

13

Analog

Mute

Analog Out

Post

Low Pass

Filter

Analog

Mute

Analog Out

Mute

Control

+5V Analog

10

11

16

18

17

BCKIN

LRCIN

DIN

SCKO

SCKI

MCKI

ML

MC

MD

V

CAP

V

ZERO

+5V Analog

Post

Low Pass

Filter

10µF

+

22

23

21

3

DGND

PGND

V

DD

V

DP

AGND

RSTB

V

CC

6

7

8

9

11

10

14

15

2

4

1

Analog

Mute

Analog Out

Post

Low Pass

Filter

Analog

Mute

Analog Out

Mute

Control

+5V Analog

12

13

19

+

10µF

+

3.3µF

+

10µF

+

+

3.3µF

10µF

+

3.3µF