CS8420 Digital Audio Sample Rate Converter Features General Description The CS8420 is a stereo digital audio sample rate con- Complete IEC60958, AES3, S/PDIF, EIAJ verter (SRC) with AES3-type and serial digital audio CP1201-compatible Transceiver with inputs, AES3-type and serial digital audio outputs, and Asynchronous Sample Rate Converter includes comprehensive control ability via a 4-wire mi- crocontroller port. Channel status and user data can be Flexible 3-wire Serial Digital I/O Ports assembled in block-sized buffers, making read/modify/write cycles easy. 8-kHz to 108-kHz Sample Rate Range Digital audio inputs and outputs may be 24, 20, or 16 1:3 and 3:1 Maximum Input to Output Sample bits. The input data can be completely asynchronous to Rate Ratio the output data, with the output data being synchronous to an external system clock. 128 dB Dynamic Range The CS8420 is available in a 28-pin SOIC package in -117 dB THD+N at 1 kHz both Commercial (-10 to +70 C) and Automotive grades (-40 to +85 C). The CDB8420 Customer Dem- Excellent Performance at Almost a 1:1 Ratio onstration board is also available for device evaluation and implementation suggestions. Excellent Clock Jitter Rejection Please refer to Ordering Information on page 93 for or- dering information. 24-bit I/O Words Target applications include CD-R, DAT, MD, DVD and Pin and Microcontroller Read/Write Access to VTR equipment, mixing consoles, digital audio trans- Channel Status and User Data mission equipment, high-quality D/A and A/D converters, effects processors, and computer audio Microcontroller and Stand-Alone Modes systems. VA+ AGND FILT RERR RMCK VD+ DGND ILRCK OLRCK Serial Sample Serial ISCLK OSCLK Audio Rate Audio Input Converter Output SDIN SDOUT RXP TXP Clock & AES3 C&Ubit AES3 Receiver Driver Data S/PDIF Data S/PDIF RXN Recovery Decoder Buffer Encoder TXN Control Output Misc. Port & Clock Control Registers Generator H/S RST EMPH U TCBL SDA/ SCL/ AD1/ AD0/ INT OMCK CDOUT CCLK CDIN CS Copyright Cirrus Logic, Inc. 2007 APRIL 07 (All Rights Reserved) 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 - IC 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 IC 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 2 DS245F4