AD7949

Data Sheet

Rev. F | Page 2 of 32

TABLE OF CONTENTS

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

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

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

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

Revision History ............................................................................... 3

Specifications..................................................................................... 4

Timing Specifications .................................................................. 6

Absolute Maximum Ratings............................................................ 8

ESD Caution.................................................................................. 8

Pin Configuration and Function Descriptions............................. 9

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

Terminology .................................................................................... 13

Theory of Operation ...................................................................... 14

Overview...................................................................................... 14

Converter Operation.................................................................. 14

Transfer Functions...................................................................... 15

Typical Connection Diagrams.................................................. 16

Analog Inputs.............................................................................. 17

Driver Amplifier Choice............................................................ 19

Voltage Reference Output/Input .............................................. 19

Power Supply............................................................................... 21

Supplying the ADC from the Reference.................................. 21

Digital Interface .............................................................................. 22

Reading/Writing During Conversion, Fast Hosts.................. 22

Reading/Writing After Conversion, Any Speed Hosts.......... 22

Reading/Writing Spanning Conversion, Any Speed Host.... 23

Configuration Register, CFG.................................................... 23

General Timing Without a Busy Indicator ............................. 25

General Timing with a Busy Indicator.................................... 26

Channel Sequencer .................................................................... 27

Read/Write Spanning Conversion Without a Busy Indicator

....................................................................................................... 28

Read/Write Spanning Conversion with a Busy Indicator..... 30

Application Hints ........................................................................... 31

Layout .......................................................................................... 31

Evaluating AD7949 Performance............................................. 31

Outline Dimensions....................................................................... 32

Ordering Guide .......................................................................... 32