Datasheet AD7685 (Analog Devices) - 3

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AD7685 Data Sheet TABLE OF CONTENTS
Features .. 1 Driver Amplifier Choice ... 16 Applications ... 1 Voltage Reference Input .. 16 Typical Application Circuit ... 1 Power Supply ... 16 General Description ... 1 Supplying the ADC from the Reference .. 17 Revision History ... 2 Digital Interface .. 17 Specifications ... 3 CS Mode 3-Wire, No BUSY Indicator ... 18 Timing Specifications ... 5 CS Mode 3-Wire with BUSY Indicator ... 19 Absolute Maximum Ratings .. 7 CS Mode 4-Wire, No BUSY Indicator ... 20 ESD Caution .. 7 CS Mode 4-Wire with BUSY Indicator ... 21 Pin Configuration and Function Descriptions ... 8 Chain Mode, No BUSY Indicator .. 22 Terminology .. 9 Chain Mode with BUSY Indicator ... 23 Typical Performance Characteristics ... 10 Application Hints ... 24 Theory of Operation .. 13 Layout .. 24 Circuit Information .. 13 Evaluating the Performance of the AD7685 ... 24 Converter Operation .. 13 True 16-Bit Isolated Application Example .. 25 Typical Connection Diagram.. 14 Outline Dimensions ... 26 Analog Inputs .. 15 Ordering Guide .. 27
REVISION HISTORY 7/14—Rev. C to Rev. D
Changes to Figure 27 .. 14 Deleted QFN .. Throughout Changes to Table 9 .. 16 Changed Application Diagram to Typical Application Changes to Figure 32 .. 17 Circuit .. 1

Changes to Figure 43 .. 22 Change to Features Section ... 1 Changes to Figure 45 .. 23 Added Patent Note, Note 1 .. 1 Updated Outline Dimensions ... 26 Changes to Evaluating the Performance of the AD7685 Changes to Ordering Guide .. 27 Section .. 24 Updated Outline Dimensions ... 26
12/04—Rev. 0 to Rev. A
Changes to Ordering Guide .. 27

Changes to Specifications ... 3 Changes to Figure 17 Captions ... 11
8/11—Rev. B to Rev. C
Changes to Power Supply Section .. 17 Changes to Figure 6 and Table 7 ... 8 Changes to Digital Interface Section ... 18 Updated Outline Dimensions ... 26 Changes to CS Mode 4-Wire No Busy Indicator Section ... 21 Changes to Ordering Guide .. 27 Changes to CS Mode 4-Wire with Busy Indicator Section ... 22 Changes to Chain Mode, No Busy Indicator Section .. 23
3/07—Rev. A to Rev. B
Changes to Chain Mode with Busy Indicator Section .. 24 Changes to Features and Table 1... 1 Added True 16-Bit Isolated Application Example Section ... 26 Changes to Table 3 .. 4 Added Figure 47 ... 26 Moved Figure 3 and Figure 4 to Page ... 6 Changes to Ordering Guide .. 28 Inserted Figure 6; Renumbered Sequentially .. 8 Changes to Figure 13 and Figure 14 ... 11
4/04—Revision 0: Initial Revision
Rev. D | Page 2 of 28 Document Outline Features Applications Typical Application Circuit General Description Table of Contents Revision History Specifications Timing Specifications Absolute Maximum Ratings ESD Caution Pin Configuration and Function Descriptions Terminology Typical Performance Characteristics Theory of Operation Circuit Information Converter Operation Transfer Functions Typical Connection Diagram Analog Inputs Driver Amplifier Choice Voltage Reference Input Power Supply Supplying the ADC from the Reference Digital Interface CS/ Mode 3-Wire, No BUSY Indicator CS/ Mode 3-Wire with BUSY Indicator CS/ Mode 4-Wire, No BUSY Indicator CS/ Mode 4-Wire with BUSY Indicator Chain Mode, No BUSY Indicator Chain Mode with BUSY Indicator Application Hints Layout Evaluating the Performance of the AD7685 True 16-Bit Isolated Application Example Outline Dimensions Ordering Guide