AD7688

Rev. A | Page 2 of 28

TABLE OF CONTENTS

Features .............................................................................................. 1

 

Applications....................................................................................... 1

 

Application Diagram........................................................................ 1

 

General Description ......................................................................... 1

 

Revision History ............................................................................... 2

 

Specifications..................................................................................... 3

 

Timing Specifications....................................................................... 5

 

Absolute Maximum Ratings............................................................ 6

 

Thermal Resistance ...................................................................... 6

 

ESD Caution.................................................................................. 6

 

Pin Configuration and Function Descriptions............................. 7

 

Terminology ...................................................................................... 8

 

Typical Performance Characteristics ............................................. 9

 

Circuit Information.................................................................... 12

 

Converter Operation.................................................................. 12

 

Typical Connection Diagram ................................................... 13

 

Analog Input ............................................................................... 14

 

Driver Amplifier Choice ........................................................... 15

 

Single-to-Differential Driver .................................................... 15

 

Voltage Reference Input ............................................................ 15

 

Power Supply............................................................................... 15

 

Supplying the ADC from the Reference.................................. 16

 

Digital Interface.......................................................................... 16

 

CS MODE 3-Wire, No BUSY Indicator .................................. 17

 

CS Mode 3-Wire with BUSY Indicator ................................... 18

 

CS Mode 4-Wire, No BUSY Indicator..................................... 19

 

CS Mode 4-Wire with BUSY Indicator ................................... 20

 

Chain Mode, No BUSY Indicator ............................................ 21

 

Chain Mode with BUSY Indicator ........................................... 22

 

Application Hints ........................................................................... 23

 

Layout .......................................................................................... 23

 

Evaluating the AD7688’s Performance.................................... 23

 

Outline Dimensions ....................................................................... 24

 

Ordering Guide .......................................................................... 25

 

REVISION HISTORY

2/11—Rev. 0 to Rev. A

Deleted QFN in Development Note............................ Throughout

Changes to Table 5............................................................................ 6

Added Thermal Resistance Section and Table 6 .......................... 6

Changes to Figure 6 and Table 7..................................................... 7

Updated Outline Dimensions ....................................................... 24

Changes to Ordering Guide .......................................................... 25

4/05—Revision 0: Initial Version