AD8420

Data Sheet

Rev. 0 | Page 2 of 28

TABLE OF CONTENTS

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

 

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

 

Pin Configuration............................................................................. 1

 

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

 

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

 

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

 

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

 

Thermal Resistance ...................................................................... 7

 

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

 

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

 

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

 

Theory of Operation ...................................................................... 19

 

Architecture................................................................................. 19

 

Setting the Gain .......................................................................... 19

 

Gain Accuracy ............................................................................ 20

 

Input Voltage Range................................................................... 20

 

Input Protection ......................................................................... 20

 

Layout .......................................................................................... 21

 

Driving the Reference Pin ......................................................... 21

 

Input Bias Current Return Path ............................................... 22

 

Radio Frequency Interference (RFI)........................................ 22

 

Output Buffering ........................................................................ 23

 

Applications Information .............................................................. 24

 

AD8420 in Electrocardiography (ECG).................................. 24

 

Classic Bridge Circuit ................................................................ 25

 

4 mA to 20 mA Single-Supply Receiver .................................. 25

 

Outline Dimensions ....................................................................... 26

 

Ordering Guide .......................................................................... 26

 

REVISION HISTORY

3/12—Revision 0: Initial Version