AD7938/AD7939

Preliminary Technical Data

TABLE OF CONTENTS

AD7938—Specifications.................................................................. 3

AD7939—Specifications.................................................................. 5

Timing Specifications....................................................................... 7

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

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

Pin Function Description ................................................................ 9

Terminology .................................................................................... 11

Typical Performance Characteristics ........................................... 13

On-Chip Registers .......................................................................... 16

Circuit Information ........................................................................ 18

Converter Operation.................................................................. 18

ADC Transfer Function............................................................. 18

Typical Connection Diagram ................................................... 19

Analog Input Structure.............................................................. 19

Analog Inputs.............................................................................. 20

Analog Input Selection .............................................................. 22

Reference Section ....................................................................... 23

Parallel Interface......................................................................... 25

Power Modes of Operation....................................................... 28

Power vs. Throughput Rate....................................................... 29

Microprocessor Interfacing....................................................... 29

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

Grounding and Layout .............................................................. 31

PCB Design Guidelines for Chip Scale Package .................... 31

Evaluating the AD7938/AD7939 Performance ...................... 31

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

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

REVISION HISTORY

8/04—Revision PrN: Preliminary Version

Rev. PrN | Page 2 of 32