SM5956A

SEIKO NPC CORPORATION —1

6-channel Asynchronous Sample Rate Converter

OVERVIEW

The SM5956A is a digital audio signal, asynchronous sample rate converter LSI. It reads 6-channel 16/20/24-

bit word length input data, and 16/20/24-bit word length output data. It also features a built-in digital deempha-

sis filter, direct muting and digital audio interface output.

FEATURES

Functions

I

L/R 6-channel processing

(2-channel stereo, 3-system processing)

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Input sample rate range: 10kHz to 200kHz

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Output sample rate range: 30kHz to 50kHz

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• 0.45 to 4.41 (SCKSLN = L, 512fso operation)

• 0.225 to 4.41 (SCKSLN = H, 768fso operation)

fso = output sample rate

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Asynchronous input timing and output timing

clock inputs

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System clock input

• Input system clock: 1fsi (LRCI)

• Output-system clock: 512fso/768fso

(input on SCK)

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Deemphasis filter function

• IIR filter structure

• 44.1kHz, 48kHz, 32kHz input sample rate fsi

compatible

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Direct mute function

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Through mode

• Input data passed directly to the outputs

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Digital audio interface output

• DIA input data undergoes sample rate conver-

sion and is output biphase mark encoded

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Output data clocks (LRCO, BCKO)

• LRCO rate: 1fso

• BCKO rate: 64fso (SCKSLN = L, 512fso operation)

48fso (SCKSLN = H, 768fso operation)

• Slave mode: Data is output at a rate dictated by

an externally input signal

• Master mode: Sample rate is generated internally

from the output-system clock, and

supplied as an output

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MCU interface

• 3-wire serial interface

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5V tolerant inputs for direct connection to 5V

devices

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3.3V single supply

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Package: 48-pin QFP

PINOUT

(Top view)

PACKAGE DIMENSIONS

(Unit: mm)

Note. Dimensions without tolerance are reference values.

ORDERING INFORMATION

Device

Package

SM5956AF

48-pin QFP

13

14

15

16

17

18

19

20

21

22

23

24

37

38

39

40

41

42

43

44

45

46

47

48

VDD

DEEMN

FS0

FS1

MCK

MDT

MLE

DMUTEN

THROUN

SLAVEN

OEDITON

VSS

VDD

TEST0

TEST1

TEST2

TEST3

SCK

VSS

SCKSLN

ERROR

RSTN

SELFN

VSS

9 ± 0.4

7 ± 0.1

0.125 − 0.025

+ 0.075

0.5

0 ~ 10

0.18

− 0.05

+ 0.09

0.08