Four ADCs/Eight DACs with PLL, 192 kHz, 24-Bit Codec AD1937 GENERAL DESCRIPTION FEATURES The AD1937 is a high performance, single-chip codec that provides PLL-generated clock or direct master clock four analog-to-digital converters (ADCs) with differential input Low EMI design and eight digital-to-analog converters (DACs) with differential 112 dB DAC/107 dB ADC dynamic range and SNR output, using the Analog Devices, Inc., patented multibit sigma- 96 dB THD + N 2 delta (-) architecture. An I C port is included, allowing a Single 3.3 V supply microcontroller to adjust volume and many other parameters. Tolerance for 5 V logic inputs The AD1937 operates from 3.3 V digital and analog supplies. Supports 24-bits and 8 kHz to 192 kHz sample rates The AD1937 is available in a 64-lead (differential output) LQFP. Differential ADC input Differential DAC output The AD1937 is designed for low EMI. This consideration is Log volume control with autoramp function apparent in both the system and circuit design architectures. 2 I C-controllable for flexibility By using the on-board PLL to derive the master clock from the Software-controllable clickless mute LR (frame) clock or from an external crystal, the AD1937 elimi- Software power-down nates the need for a separate high frequency master clock and 2 Right-justified, left-justified, I S, and TDM modes can also be used with a suppressed bit clock. The DACs and Master and slave modes up to 16-channel input/output ADCs are designed using the latest Analog Devices continuous Available in a 64-lead LQFP time architecture to further minimize EMI. By using 3.3 V Qualified for automotive applications supplies, power consumption is minimized and further reduces emissions. APPLICATIONS Automotive audio systems Home theater systems Set-top boxes Digital audio effects processors FUNCTIONAL BLOCK DIAGRAM DIGITAL AUDIO INPUT/OUTPUT AD1937 SERIAL DATA PORT DAC DAC SDATA SDATA ADC DAC OUT IN DIGITAL ADC ANALOG CLOCKS FILTER DAC ANALOG DIGITAL AUDIO AND AUDIO FILTER INPUTS VOLUME OUTPUTS DAC ADC CONTROL TIMING MANAGEMENT AND CONTROL DAC ADC (CLOCK AND PLL) DAC DAC 2 I C PRECISION CONTROL PORT VOLTAGE REFERENCE CONTROL DATA INPUT/OUTPUT Figure 1. Rev. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 www.analog.com license is granted by implication or otherwise under any patent or patent rights of Analog Devices. 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Trademarks and registered trademarks are the property of their respective owners. 07414-001AD1937 TABLE OF CONTENTS Features .............................................................................................. 1 Analog-to-Digital Converters (ADCs) .................................... 15 Applications ....................................................................................... 1 Digital-to-Analog Converters (DACs) .................................... 15 General Description ......................................................................... 1 Clock Signals ............................................................................... 15 Functional Block Diagram .............................................................. 1 Reset and Power-Down ............................................................. 16 2 Revision History ............................................................................... 2 I C Control Port .......................................................................... 16 Specif icat ions ..................................................................................... 3 Power Supply and Voltage Reference ....................................... 18 Test Conditions ............................................................................. 3 Serial Data PortsData Format ............................................... 19 Analog Performance Specifications ........................................... 3 Time-Division Multiplexed (TDM) Modes ............................ 20 Crystal Oscillator Specifications................................................. 5 Daisy-Chain Mode ..................................................................... 23 Digital Specifications ................................................................... 6 Additional Modes ....................................................................... 26 Power Supply Specifications........................................................ 6 Control Registers ............................................................................ 27 Digital Filters ................................................................................. 7 Def initions ................................................................................... 27 Timing Specifications .................................................................. 8 PLL and Clock Control Registers ............................................. 27 Timing Diagrams .......................................................................... 9 DAC Control Registers .............................................................. 28 Absolute Maximum Ratings .......................................................... 10 ADC Control Registers .............................................................. 30 Thermal Resistance .................................................................... 10 Applications Circuits ...................................................................... 32 ESD Caution ................................................................................ 10 Outline Dimensions ....................................................................... 33 Pin Configuration and Function Descriptions ........................... 11 Ordering Guide .......................................................................... 33 Typical Performance Characteristics ........................................... 13 Automotive Products ................................................................. 33 Theory of Operation ...................................................................... 15 REVISION HISTORY 6/10Rev. A to Rev. B Changes to Table 3 Introductory Text and to Table 3 .................. 4 Changes to Table 5 Introductory Text ........................................... 6 Changes to Table 8 Introductory Text ........................................... 8 3/10Rev. 0 to Rev. A Changes to Ordering Guide .......................................................... 33 9/08Revision 0: Initial Version Rev. B Page 2 of 36