WM8775

w DESCRIPTION The WM8775 is a high performance, stereo audio ADC with a 4 channel input mixer. The WM8775 is ideal for digitising multiple analogue sources for surround sound processing applications for home hi-fi, automotive and other audio visual equipment. A stereo 24-bit multi-bit sigma delta ADC is used with a four stereo channel input selector. Each channel has programmable gain control. Digital audio output word lengths from 16-32 bits and sampling rates from 32kHz to 96kHz are supported. The audio data interface supports I S, left justified, right justified and DSP digital audio formats. The device is controlled via a 2 or 3 wire serial interface. The interface provides access to all features including channel selection, volume controls, mutes, de-emphasis and power management facilities. The device is available in a 28-pin SSOP package. The WM8775 is software compatible with the WM8776. 2 WM8775 24-bit, 96kHz ADC with 4 Channel I/P Multiplexer FEATURES • Audio Performance − 102dB SNR (‘A’ weighted @ 48kHz) − -90dB THD ADC Sampling Frequency: 32kHz – 96kHz Four stereo ADC inputs with analogue gain adjust from +24dB to –21dB in 0.5dB steps Digital gain adjust from -21.5dB to -103dB. Programmable Automatic Level Control (ALC) or Limiter on ADC input 3-Wire SPI Compatible or 2-wire Serial Control Interface Master or Slave Clocking Mode Programmable Audio Data Interface Modes − I2S, Left, Right Justified or DSP − 16/20/24/32 bit Word Lengths 2.7V to 5.5V Analogue, 2.7V to 3.6V Digital supply Operation 5V tolerant digital inputs • • • • • • • • • APPLICATIONS • • Surround Sound AV Processors and Hi-Fi systems Automotive Audio BLOCK DIAGRAM ADCREFGND ADCREFP VMIDADC AGND AVDD AINOPL AINOPR AINVGL AINVGR W WM8775 AIN1L AIN1R AIN2L AIN2R AIN3L AIN3R AIN4L AIN4R INPUT MIXER AUDIO INTERFACE STEREO ADC VMID ALC AND DIGITAL FILTERS MCLK DOUT ADCLRC BCLK CONTROL INTERFACE MODE CE WOLFSON MICROELECTRONICS plc w :: www.wolfsonmicro.com DGND DVDD CL DI Product Preview, June 2004, Rev 1.8 Copyright 2004 Wolfson Microelectronics plc WM8775 TABLE OF CONTENTS Product Preview DESCRIPTION ................................................................................................................1 FEATURES......................................................................................................................1 BLOCK DIAGRAM ..........................................................................................................1 PIN CONFIGURATION....................................................................................................3 ORDERING INFORMATION ...........................................................................................3 PIN DESCRIPTION .........................................................................................................4 ABSOLUTE MAXIMUM RATINGS..................................................................................5 RECOMMENDED OPERATING CONDITIONS ..............................................................5 ELECTRICAL CHARACTERISTICS ...............................................................................6 TERMINOLOGY ......................................................................................................................7 MASTER CLOCK TIMING...............................................................................................7 DIGITAL AUDIO INTERFACE – MASTER MODE ...................................................................7 DIGITAL AUDIO INTERFACE – SLAVE MODE ......................................................................8 3-WIRE MPU INTERFACE TIMING ......................................................................................10 2-WIRE MPU INTERFACE TIMING ......................................................................................10 DEVICE DESCRIPTION................................................................................................12 INTRODUCTION ...................................................................................................................12 AUDIO DATA SAMPLING RATES.........................................................................................12 POWERDOWN MODES .......................................................................................................13 POWER-ON-RESET .............................................................................................................14 DIGITAL AUDIO INTERFACE ...............................................................................................15 CONTROL INTERFACE OPERATION ..................................................................................18 CONTROL INTERFACE REGISTERS ..................................................................................19 LIMITER / AUTOMATIC LEVEL CONTROL (ALC) ................................................................23 REGISTER MAP ...................................................................................................................28 DIGITAL FILTER CHARACTERISTICS ........................................................................32 ADC FILTER RESPONSES...................................................................................................32 ADC HIGH PASS FILTER .....................................................................................................32 APPLICATIONS INFORMATION ..................................................................................33 EXTERNAL CIRCUIT CONFIGURATION .............................................................................33 RECOMMENDED EXTERNAL COMPONENTS ....................................................................34 IMPORTANT NOTICE ...................................................................................................36 ADDRESS: ............................................................................................................................36 w PP Rev 1.8, June 2004 2 Product Preview WM8775 PIN CONFIGURATION AIN1L BCLK MCLK DOUT ADCLRC DGND DVDD MODE CE DI CL NC VMIDADC ADCREFGND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 AIN1R AIN2L AIN2R AIN3L AIN3R AIN4L AIN4R AINOPL AINVGL AINOPR AINVGR AGND AVDD ADCREFP ORDERING INFORMATION DEVICE W M8775EDS W M8775EDS/R W M8775SEDS W M8775SEDS/R Note: Reel quantity = 2,000 TEMP. RANGE -25 to +85oC -25 to +85oC -25 to +85oC -25 to +85 C o PACKAGE 28-pin SSOP 28-pin SSOP (tape and reel) 28-pin SSOP (lead free) 28-pin SSOP (lead free, tape and reel) MOISTURE SENSITIVITY LEVEL MSL1 MSL1 MSL1 MSL1 PEAK SOLDERING TEMP 240°C 240°C 260°C 260°C w PP Rev 1.8, June 2004 3 WM8775 PIN DESCRIPTION PIN 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 VMIDADC ADCREFGND ADCREFP AVDD AGND AINVGR AINOPR AINVGL AINOPL AIN4R AIN4L AIN3R AIN3L AIN2R AIN2L AIN1R NAME AIN1L BCLK MCLK DOUT ADCLRC DGND DVDD MODE CE DI CL TYPE Analogue Input Digital input/output Digital input Digital output Digital input/output Supply Supply Digital Input Digital Input Digital input/output Digital input NC Analogue Output Supply Analogue Output Supply Supply Analogue Input Analogue Output Analogue Input Analogue Output Analogue Input Analogue Input Analogue Input Analogue Input Analogue Input Analogue Input Analogue Input ADC audio interface bit clock DESCRIPTION Channel 1 left input multiplexor virtual ground Product Preview Master ADC clock; 256, 384, 512 or 768fs (fs = word clock frequency) ADC data output ADC left/right word clock Digital negative supply Digital positive supply Serial Interface Mode select (5V tolerant) Serial Interface Latch signal (5V tolerant) Serial interface data (5V tolerant) Serial interface clock (5V tolerant) No connection ADC midrail divider decoupling pin; 10uF external decoupling ADC negative supply and substrate connection ADC positive reference decoupling pin; 10uF external decoupling Analogue positive supply Analogue negative supply and substrate connection Right channel multiplexor virtual ground Right channel multiplexor output Left channel multiplexor virtual ground Left channel multiplexor output Channel 4 right input multiplexor virtual ground Channel 4 left input multiplexor virtual ground Channel 3 right input multiplexor virtual ground Channel 3 left input multiplexor virtual ground Channel 2 right input multiplexor virtual ground Channel 2 left input multiplexor virtual ground Channel 1 right input multiplexor virtual ground Note : Digital input pins have Schmitt trigger input buffers and pins 8, 9, 10 and 11 are 5V tolerant. w PP Rev 1.8, June 2004 4 Product Preview WM8775 ABSOLUTE MAXIMUM RATINGS Absolute Maximum Ratings are stress ratings only. Permanent damage to the device may be caused by continuously operating at or beyond these limits. Device functional operating limits and guaranteed performance specifications are given under Electrical Characteristics at the test conditions specified. ESD Sensitive Device. This device is manufactured on a CMOS process. It is therefore generically susceptible to damage from excessive static voltages. Proper ESD precautions must be taken during handling and storage of this device. Wolfson tests its package types according to IPC/JEDEC J-STD-020B for Moisture Sensitivity to determine acceptable storage conditions prior to surface mount assembly. These levels are: MSL1 = unlimited floor life at