AD7739

Data Sheet

Rev. A | Page 2 of 32

TABLE OF CONTENTS

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

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

Functional Block Diagram .............................................................. 1

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

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

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

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

Timing Diagrams.......................................................................... 6

Absolute Maximum Ratings............................................................ 7

ESD Caution.................................................................................. 7

Pin Configuration and Function Descriptions............................. 8

Typical Performance Characteristics ........................................... 10

Output Noise and Resolution Specification................................ 11

Chopping Enabled...................................................................... 11

Chopping Disabled..................................................................... 12

Register Descriptions ..................................................................... 13

Register Access............................................................................ 14

Communications Register......................................................... 14

I/O Port Register......................................................................... 15

Revision Register ........................................................................ 15

Test Register ................................................................................ 15

ADC Status Register................................................................... 15

Checksum Register..................................................................... 16

ADC Zero-Scale Calibration Register ..................................... 16

ADC Full-Scale Calibration Register....................................... 16

Channel Data Registers.............................................................. 16

Channel Zero-Scale Calibration Registers.............................. 16

Channel Full-Scale Calibration Registers ............................... 16

Channel Status Registers ........................................................... 17

Channel Setup Registers............................................................ 18

Channel Conversion Time Registers ....................................... 19

Mode Register............................................................................. 19

Digital Interface Description ........................................................ 21

Hardware ..................................................................................... 21

Reset............................................................................................. 22

Access the AD7739 Registers.................................................... 22

Single Conversion and Reading Data...................................... 22

Dump Mode................................................................................ 22

Continuous Conversion Mode ................................................. 23

Continuous Read (Continuous Conversion) Mode .............. 24

Circuit Description......................................................................... 25

Analog Inputs.............................................................................. 25

Sigma-Delta ADC ...................................................................... 25

Chopping..................................................................................... 25

Multiplexer, Conversion, and Data Output Timing .............. 26

Frequency Response .................................................................. 27

Extended Voltage Range of the Analog Input ........................ 27

Voltage Reference Inputs........................................................... 28

Reference Detect......................................................................... 28

I/O Port........................................................................................ 28

Calibration................................................................................... 28

Outline Dimensions....................................................................... 30

Ordering Guide .......................................................................... 30

REVISION HISTORY

8/13—Rev. 0 to Rev. A

Updated Format..................................................................Universal

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

Change to ADC Performance Chopping Enabled, Integral

Nonlinearity Parameter, Table 1 ..................................................... 3

Change to Table 3 ............................................................................. 7

Deleted Figure 12, Renumbered Sequentially .............................. 8

Changes to Revision Register Section.......................................... 15

Change to Voltage Reference Inputs Section .............................. 28

Updated Outline Dimensions....................................................... 30

Changes to Ordering Guide .......................................................... 30

5/03—Revision 0: Initial Version