CS3318 8-Channel Analog Volume Control Features Description Complete Analog Volume Control The CS3318 is an 8-channel digitally controlled analog 8 Independently Controllable Channels volume control designed specifically for high-end audio 3 Configurable Master Volume and Muting systems. It features a comprehensive IC/SPI serial control port for easy device and volume configuration. Controls Wide Adjustable Volume Range The CS3318 includes arrays of well-matched resistors and complementary low-noise active output stages. A -96 dB to +22 dB in dB Steps total adjustable range of 118dB, in dB steps, is Low Distortion & Noise spread evenly over 96 dB of attenuation and 22 dB of -112 dB THD+N gain. 127 dB Dynamic Range The CS3318 implements configurable zero-crossing Noise-Free Level Transitions detection to provide glitch-free volume-level changes. Zero-Crossing Detection with The IC/SPI control interface provides for easy system Programmable Time-Out integration of up to 128 CS3318 devices over a single 2- wire IC or 3-wire SPI bus, allowing many channels of Low Channel-to-Channel Crosstalk volume control with minimal system controller I/O re- 120 dB Inter-Channel Isolation quirements. Devices may be controlled on an individual Comprehensive Serial Control Port and grouped basis, simplifying simultaneous configura- TM Supports IC and SPI Communication tion of a group of channels across multiple devices, while allowing discrete control over all channels on an Independent Control of up to 128 Devices individual basis. on a Shared 2-Wire IC or 3-Wire SPI Control Bus The device operates from 8 V to 9 V analog supplies Supports Individual and Grouped Control of and has an input/output voltage range of 6.65 V to 7.65 V. The digital control interface operates at +3.3 V. all CS3318 Devices on the IC or SPI Control Bus The CS3318 is available in a 48-pin LQFP package in Commercial grade (-10 to 70 C). The CS3318 Cus- Flexible Power Supply Voltages tomer Demonstration board is also available for device 8 V to 9 V Analog Supply evaluation. Refer to Ordering Information on page 44 +3.3 V Digital Supply for complete details. 8 V to 9 V 8-Channel 8 Analog Inputs +3.3 V + 8-Channel 8 Analog IC / SPI IC/SPI Outputs Control Serial Port Control Zero Crossing Detector Copyright Cirrus Logic, Inc. 2006 DECEMBER 06 (All Rights Reserved) CS3318 TABLE OF CONTENTS 1. PIN DESCRIPTIONS ............................................................................................................................ 5 2. CHARACTERISTICS AND SPECIFICATIONS .................................................................................... 7 SPECIFIED OPERATING CONDITIONS .................................................................................................... 7 ABSOLUTE MAXIMUM RATINGS............................................................................................................... 7 ANALOG CHARACTERISTICS ................................................................................................................... 8 DIGITAL INTERFACE CHARACTERISTICS...............................................................................................9 MUTE SWITCHING CHARACTERISTICS ..................................................................................................9 CONTROL PORT SWITCHING CHARACTERISTICS - IC FORMAT...................................................... 10 CONTROL PORT SWITCHING CHARACTERISTICS - SPI FORMAT ................................................. 11 3. TYPICAL CONNECTION DIAGRAM ................................................................................................. 12 4. DETAILED BLOCK DIAGRAM .......................................................................................................... 13 5. APPLICATIONS ................................................................................................................................. 14 5.1 General Description ..................................................................................................................... 14 5.2 System Design ............................................................................................................................ 14 5.2.1 Analog Inputs .................................................................................................................... 14 5.2.2 Analog Outputs .................................................................................................................. 15 5.2.3 Recommended Layout, Grounding, and Power Supply Decoupling ................................. 15 5.3 Power-Up and Power-Down ........................................................................................................ 15 5.3.1 Recommended Power-Up Sequence ................................................................................ 16 5.3.2 Recommended Power-Down Sequence ........................................................................... 16 5.4 Volume & Muting Control Architecture ........................................................................................ 17 5.4.1 Control Mapping Matrix ..................................................................................................... 17 5.4.2 Volume & Muting Control Implementation ......................................................................... 18 5.5 Volume Controls .......................................................................................................................... 19 5.5.1 Individual Channel Volume Controls ................................................................................. 19 5.5.2 Master Volume Controls .................................................................................................... 19 5.5.3 Volume Limits .................................................................................................................... 20 5.6 Muting Controls ........................................................................................................................... 21 5.6.1 Individual Channel Mute Controls ..................................................................................... 21 5.6.2 Master Mute Controls ........................................................................................................ 21 5.6.3 Hardware Mute Control ..................................................................................................... 21 5.7 Zero-Crossing Detection .............................................................................................................. 22 5.7.1 Zero-Crossing Modes ........................................................................................................ 22 5.7.2 Zero-Crossing Time-Out .................................................................................................... 22 5.8 System Serial Control Configuration ........................................................................................... 23 5.8.1 Serial Control within a Single-CS3318 System .................................................................23 5.8.2 Serial Control within a Multiple-CS3318 System ............................................................... 24 5.8.2.1 SPI Mode Serial Control Configuration .......................................................................................... 24 5.8.2.2 IC Mode Control Configuration ..................................................................................................... 26 5.9 IC/SPI Serial Control Formats .................................................................................................... 27 5.9.1 IC Mode ............................................................................................................................ 27 5.9.2 SPI Mode ........................................................................................................................... 28 6. CS3318 REGISTER QUICK REFERENCE ........................................................................................ 29 7. CS3318 REGISTER DESCRIPTIONS ................................................................................................ 31 7.1 Ch 1-8 Volume - Addresses 01h - 08h ........................................................................................ 31 7.1.1 Volume Control (Bits 7:0) .................................................................................................. 31 7.2 dB Control - Address 09h ........................................................................................................ 32 7.2.1 dB Control (Bit 0 - 7) ...................................................................................................... 32 7.3 Mute Control - Address 0Ah ........................................................................................................ 33 7.3.1 Mute Channel X (Bit 0 - 7) ................................................................................................. 33 7.4 Device Configuration 1 - Address 0Bh (Bit 5) ..............................................................................33 7.4.1 Enable MUTE Input (Bit 5) ................................................................................................ 33 2 DS693F1