Datasheet

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