AD7690

Data Sheet

TABLE OF CONTENTS

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

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

Application Example ........................................................................ 1

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

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

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

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

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

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

Pin Configurations and Function Descriptions ........................... 7

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

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

Theory of Operation ...................................................................... 12

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

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

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

Analog Inputs.............................................................................. 14

Driver Amplifier Choice ........................................................... 14

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

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

Power Supply............................................................................... 16

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

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

CS Mode, 3-Wire Without Busy Indicator ............................. 17

CS Mode, 3-Wire With Busy Indicator ................................... 18

CS Mode, 4-Wire Without Busy Indicator ............................. 19

CS Mode, 4-Wire With Busy Indicator ................................... 20

Chain Mode Without Busy Indicator ...................................... 21

Chain Mode with Busy Indicator............................................. 22

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

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

Evaluating the AD7690 Performance ...................................... 23

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

Ordering Guide .......................................................................... 24

REVISION HISTORY

7/14—Rev. B to Rev. C

Changed QFN (LFCSP) to LFCSP .............................. Throughout

Changes to Features Section............................................................ 1

Added Patent Note, Note 1.............................................................. 1

Changes to Evaluating the AD7690 Performance Section........ 23

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

Changes to Ordering Guide .......................................................... 24

7/11—Rev. A to Rev. B

Changes to Common-Mode Input Range Min Parameter ......... 3

Added EPAD Note to Figure 6 and Table 6................................... 7

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

Changes to Ordering Guide .......................................................... 24

3/07—Rev. 0 to Rev. A

Removed Endnote Regarding QFN Package ..................Universal

Changes to Features.......................................................................... 1

Changes to Table 1............................................................................ 1

Changes to Figure 2.......................................................................... 1

Changes to Gain Error in Table 2....................................................3

Change to Gain Error Temperature Drift in Table 2 ....................3

Change to Zero Temperature Drift in Table 2 ...............................3

Changes to Power Dissipation in Table 3.......................................4

Change to Conversion Time: CNV Rising Edge to Data

Available in Table 4............................................................................5

Change to Acquisition Time in Table 4..........................................5

Changes to Figure 12.........................................................................9

Change to Figure 22 Caption........................................................ 11

Changes to Circuit Information Section ..................................... 12

Change to Table 7 ........................................................................... 13

Change to Endnote 1 of Figure 26................................................ 13

Added Figure 29 ............................................................................. 14

Changes to Driver Amplifier Choice Section............................. 14

Change to Evaluating the AD7690’s Performance Section....... 23

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

Changes to Ordering Guide.......................................................... 24

4/06—Revision 0: Initial Version

Rev. C | Page 2 of 24