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Digital Audio Sample Rate Converter

Features

 Complete IEC60958, AES3, S/PDIF, EIAJ

CP1201-compatible Transceiver with

Asynchronous Sample Rate Converter

 Flexible 3-wire Serial Digital I/O Ports

 8-kHz to 108-kHz Sample Rate Range

 1:3 and 3:1 Maximum Input to Output Sample

Rate Ratio

 128 dB Dynamic Range

 -117 dB THD+N at 1 kHz

 Excellent Performance at Almost a 1:1 Ratio

 Excellent Clock Jitter Rejection

 24-bit I/O Words

 Pin and Microcontroller Read/Write Access to

Channel Status and User Data

 Microcontroller and Stand-Alone Modes

General Description

The CS8420 is a stereo digital audio sample rate con-

verter (SRC) with AES3-type and serial digital audio

inputs, AES3-type and serial digital audio outputs, and

includes comprehensive control ability via a 4-wire mi-

crocontroller port. Channel status and user data can be

assembled in block-sized buffers, making

read/modify/write cycles easy.

Digital audio inputs and outputs may be 24, 20, or 16

bits. The input data can be completely asynchronous to

the output data, with the output data being synchronous

to an external system clock.

The CS8420 is available in a 28-pin SOIC package in

both Commercial (-10º to +70º C) and Automotive

grades (-40º to +85º C). The CDB8420 Customer Dem-

onstration board is also available for device evaluation

and implementation suggestions.

Please refer to “Ordering Information” on page 93 for or-

dering information.

Target applications include CD-R, DAT, MD, DVD and

VTR equipment, mixing consoles, digital audio trans-

mission equipment, high-quality D/A and A/D

converters, effects processors, and computer audio

systems.

Serial

Audio

Input

Clock &

Data

Recovery

Misc.

Control

AES3

S/PDIF

Encoder

Serial

Audio

Output

Receiver

AES3

S/PDIF

Decoder

Sample

Rate

Converter

C&Ubit

Data

Buffer

Control

Port &

Registers

Output

Clock

Generator

RXN

RXP

ILRCK

ISCLK

SDIN

OLRCK

OSCLK

SDOUT

TXP

TXN

RST OMCKEMPH U TCBL SDA/

CDOUT

SCL/

CCLK

AD1/

CDIN

AD0/

INT

VA+

AGND

FILT RERR VD+

DGND

H/S

RMCK

Driver

APRIL '07

DS245F4

CS8420

2 DS245F4

CS8420

TABLE OF CONTENTS

1. CHARACTERISTICS AND SPECIFICATIONS ...................................................................................... 6

SPECIFIED OPERATING CONDITIONS .............................................................................................. 6

ABSOLUTE MAXIMUM RATINGS ........................................................................................................ 6

PERFORMANCE SPECIFICATIONS .................................................................................................... 7

DIGITAL FILTER CHARACTERISTICS .................................................................................................7

DC ELECTRICAL SPECIFICATIONS .................................................................................................... 7

DIGITAL INPUT CHARACTERISTICS ..................................................................................................8

DIGITAL INTERFACE SPECIFICATIONS ............................................................................................. 8

TRANSMITTER CHARACTERISTICS .................................................................................................. 8

SWITCHING CHARACTERISTICS ....................................................................................................... 8

SWITCHING CHARACTERISTICS - SERIAL AUDIO PORTS .............................................................. 9

SWITCHING CHARACTERISTICS - CONTROL PORT - SPI™ MODE ............................................. 10

SWITCHING CHARACTERISTICS - CONTROL PORT - I²C® MODE ............................................... 11

2. TYPICAL CONNECTION DIAGRAM ................................................................................................... 12

3. GENERAL DESCRIPTION ................................................................................................................... 13

4. DATA I/O FLOW AND CLOCKING OPTIONS ..................................................................................... 14

5. SAMPLE RATE CONVERTER (SRC) .................................................................................................. 18

5.1 Dither ............................................................................................................................................. 18

5.2 SRC Locking, Varispeed and the Sample Rate Ratio Register ..................................................... 18

6. THREE-WIRE SERIAL AUDIO PORTS ...............................................................................................19

7. AES3 TRANSMITTER AND RECEIVER .............................................................................................. 22

7.1 AES3 Receiver ............................................................................................................................... 22

7.1.1 PLL, Jitter Attenuation, and Varispeed .................................................................................. 22

7.1.2 OMCK Out On RMCK ........................................................................................................... 22

7.1.3 Error Reporting and Hold Function ........................................................................................22

7.1.4 Channel Status Data Handling .............................................................................................. 23

7.1.5 User Data Handling ............................................................................................................... 23

7.1.6 Non-Audio Auto Detection ..................................................................................................... 24

7.2 AES3 Transmitter ........................................................................................................................... 24

7.2.1 Transmitted Frame and Channel Status Boundary Timing ................................................... 24

7.2.2 TXN and TXP Drivers ............................................................................................................ 25

7.3 Mono Mode Operation ................................................................................................................... 25

8. AES3 TRANSMITTER AND RECEIVER .............................................................................................. 28

8.1 Sample Rate Converter ................................................................................................................. 28

8.2 Non-SRC Delay ............................................................................................................................. 29

9. CONTROL PORT DESCRIPTION AND TIMING ................................................................................. 30

9.1 SPI Mode ....................................................................................................................................... 30

9.2 I²C Mode ........................................................................................................................................ 31

9.3 Interrupts ........................................................................................................................................ 31

10. CONTROL PORT REGISTER BIT DEFINITIONS ............................................................................. 32

10.1 Memory Address Pointer (MAP) .............................................................................................

..... 32

10.2 Miscellaneous Control 1 (01h) ..................................................................................................... 34

10.3 Miscellaneous Control 2 (02h) ..................................................................................................... 35

10.4 Data Flow Control (03h) ............................................................................................................... 36

10.5 Clock Source Control (04h) .......................................................................................................... 37

10.6 Serial Audio Input Port Data Format (05h) ................................................................................... 38

10.7 Serial Audio Output Port Data Format (06h) ................................................................................39

10.8 Interrupt 1 Register Status (07h) (Read Only) .............................................................................40

10.9 Interrupt Register 2 Status (08h) (Read Only) .............................................................................41

10.10 Interrupt 1 Register Mask (09h) ................................................................................................. 41

10.11 Interrupt Register 1 Mode Registers MSB & LSB (0Ah,0Bh) ..................................................... 41

10.12 Interrupt 2 Register Mask (0Ch) ................................................................................................. 42

DS245F4 3

CS8420

10.13 Interrupt Register 2 Mode Registers MSB & LSB (0Dh,0Eh) ..................................................... 42

10.14 Receiver Channel Status (0Fh) (Read Only) ............................................................................. 43

10.15 Receiver Error (10h) (Read Only) .............................................................................................. 44

10.16 Receiver Error Mask (11h) ......................................................................................................... 45

10.17 Channel Status Data Buffer Control (12h) .................................................................................45

10.18 User Data Buffer Control (13h) .................................................................................................. 46

10.19 Sample Rate Ratio (1Eh) (Read Only) ....................................................................................... 47

10.20 C-Bit or U-Bit Data Buffer (20h - 37h) ........................................................................................ 47

10.21 CS8420 I.D. and Version Register (7Fh) (Read Only) ............................................................... 47

11. SYSTEM AND APPLICATIONS ISSUES ........................................................................................... 48

11.1 Reset, Power Down and Start-up Options ................................................................................... 48

11.2 Transmitter Startup ...................................................................................................................... 48

11.3 SRC Invalid State ......................................................................................................................... 49

11.4 C/U Buffer Data Corruption .......................................................................................................... 49

11.5 Block-Mode U-Data D-to-E Buffer Transfers ............................................................................... 50

11.6 ID Code and Revision Code ........................................................................................................ 50

11.7 Power Supply, Grounding, and PCB layout ................................................................................. 50

11.8 Synchronization of Multiple CS8420s .......................................................................................... 50

11.9 Extended Range Sample Rate Conversion ................................................................................. 50

12. SOFTWARE MODE - PIN DESCRIPTION ......................................................................................... 51

13. HARDWARE MODES ......................................................................................................................... 55

13.1 Overall Description ....................................................................................................................... 55

13.1.1 Hardware Mode Definitions ................................................................................................. 55

13.1.2 Serial Audio Port Formats ................................................................................................... 55

13.2 Hardware Mode 1 Description (DEFAULT Data Flow, AES3 Input) ............................................ 56

13.2.1 Pin Description - Hardware Mode 1 .................................................................................... 57

13.3 Hardware Mode 2 Description ..................................................................................................... 59

13.3.1 Pin Description - Hardware Mode 2 .................................................................................... 61

13.4 Hardware Mode 3 Description ..................................................................................................... 63

13.4.1 Pin Description - Hardware Mode 3 .................................................................................... 65

13.5 Hardware Mode 4 Description ..................................................................................................... 67

13.5.1 Pin Description - Hardware Mode 4 .................................................................................... 69

13.6 Hardware Mode 5 Description ..................................................................................................... 71

13.6.1 Pin Description - Hardware Mode 5 .................................................................................... 72

13.7 Hardware Mode 6 Description ..............................................................................................

....... 74

13.7.1 Pin Description - Hardware Mode 6 .................................................................................... 76

14. EXTERNAL AES3/SPDIF/IEC60958 TRANSMITTER AND RECEIVER COMPONENTS ................ 78

14.1 AES3 Transmitter External Components ..................................................................................... 78

14.2 AES3 Receiver External Components .........................................................................................79

14.3 Isolating Transformer Requirements ............................................................................................ 80

15. CHANNEL STATUS AND USER DATA BUFFER MANAGEMENT .................................................. 81

15.1 AES3 Channel Status(C) Bit Management .................................................................................. 81

15.1.1 Manually Accessing the E Buffer .........................................................................................82

15.1.2 Reserving the First 5 Bytes in the E Buffer ......................................................................... 83

15.1.3 Serial Copy Management System (SCMS) ......................................................................... 83

15.1.4 Channel Status Data E Buffer Access ................................................................................. 83

15.1.5 One-Byte Mode ................................................................................................................... 84

15.1.6 Two-Byte Mode ................................................................................................................... 84

15.2 AES3 User (U) Bit Management .................................................................................................. 84

15.2.1 Mode 1: Transmit All Zeros ................................................................................................. 84

15.2.2 Mode 2: Block Mode ............................................................................................................ 84

15.2.3 IEC60958 Recommended U Data Format for Consumer Applications ............................... 85

15.2.4 Mode (3): Reserved ............................................................................................................. 85

15.2.5 Mode (4): IEC Consumer B ................................................................................................. 85

Part #	CS8420-CS
Description	Sample Rate Converter 28-PinSOIC Rail - Rail/Tube
Category	IC
Availability	Out of Stock
Qty	0

CS8420-CS

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